@misc{swaisgood_2005, title={The importance of disulfide bridging}, volume={23}, ISSN={["0734-9750"]}, DOI={10.1016/j.biotechadv.2004.09.004}, number={1}, journal={BIOTECHNOLOGY ADVANCES}, author={Swaisgood, HE}, year={2005}, month={Jan}, pages={71–73} }
 @article{truong_clare_catignani_swaisgood_2004, title={Cross-linking and rheological changes of whey proteins treated with microbial transglutaminase}, volume={52}, ISSN={["1520-5118"]}, DOI={10.1021/jf034397c}, abstractNote={Modification of the functionality of whey proteins using microbial transglutaminase (TGase) has been the subject of recent studies. However, changes in rheological properties of whey proteins as affected by extensive cross-linking with TGase are not well studied. The factors affecting cross-linking of whey protein isolate (WPI) using both soluble and immobilized TGase were examined, and the rheological properties of the modified proteins were characterized. The enzyme was immobilized on aminopropyl glass beads (CPG-3000) by selective adsorption of the biotinylated enzyme on avidin that had been previously immobilized. WPI (4 and 8% w/w) in deionized water, pH 7.5, containing 10 mM dithiothreitol was cross-linked using enzyme/substrate ratios of 0.12-10 units of activity/g WPI. The reaction was carried out in a jacketed bioreactor for 8 h at 40 degrees C with continuous circulation. The gel point temperature of WPI solutions treated with 0.12 unit of immobilized TGase/g was slightly decreased, but the gel strength was unaffected. However, increasing the enzyme/substrate ratio resulted in extensive cross-linking of WPI that was manifested by increases in apparent viscosity and changes in the gelation properties. For example, using 10 units of soluble TGase/g resulted in extensive cross-linking of alpha-lactalbumin and beta-lactoglobulin in WPI, as evidenced by SDS-PAGE and Western blotting results. Interestingly, the gelling point of WPI solutions increased from 68 to 94 degrees C after a 4-h reaction, and the gel strength was drastically decreased (lower storage modulus, G'). Thus, extensive intra- and interchain cross-linking probably caused formation of polymers that were too large for effective network development. These results suggest that a process could be developed to produce heat-stable whey proteins for various food applications.}, number={5}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Truong, VD and Clare, DA and Catignani, GL and Swaisgood, HE}, year={2004}, month={Mar}, pages={1170–1176} }
 @misc{farrell_jimenez-flores_bleck_brown_butler_creamer_hicks_hollar_ng-kwai-hang_swaisgood_2004, title={Nomenclature of the proteins of cows' milk - Sixth revision}, volume={87}, ISSN={["1525-3198"]}, DOI={10.3168/jds.S0022-0302(04)73319-6}, abstractNote={This report of the American Dairy Science Association Committee on the Nomenclature, Classification, and Methodology of Milk Proteins reviews changes in the nomenclature of milk proteins necessitated by recent advances of our knowledge of milk proteins. Identification of major caseins and whey proteins continues to be based upon their primary structures. Nomenclature of the immunoglobulins consistent with new international standards has been developed, and all bovine immunoglobulins have been characterized at the molecular level. Other significant findings related to nomenclature and protein methodology are elucidation of several new genetic variants of the major milk proteins, establishment by sequencing techniques and sequence alignment of the bovine caseins and whey proteins as the reference point for the nomenclature of all homologous milk proteins, completion of crystallographic studies for major whey proteins, and advances in the study of lactoferrin, allowing it to be added to the list of fully characterized milk proteins.}, number={6}, journal={JOURNAL OF DAIRY SCIENCE}, author={Farrell, HM and Jimenez-Flores, R and Bleck, GT and Brown, EM and Butler, JE and Creamer, LK and Hicks, CL and Hollar, CM and Ng-Kwai-Hang, KF and Swaisgood, HE}, year={2004}, month={Jun}, pages={1641–1674} }
 @misc{fasina_swaisgood_garlich_classen_2004, title={Rebuttal on a semi-pilot-scale procedure for isolating and purifying soybean (Glycine max) lectin}, volume={52}, ISSN={["0021-8561"]}, DOI={10.1021/jf0401367}, abstractNote={ADVERTISEMENT RETURN TO ISSUEPREVCorrespondenceNEXTRebuttal on A Semi-Pilot-Scale Procedure for Isolating and Purifying Soybean (Glycine max) LectinYewande O. Fasina, Harold E. Swaisgood, Jim D. Garlich, and Henry L. ClassenView Author Information Department of Poultry Science, Auburn University, Auburn, Alabama 36849; Departments of Food Science and Poultry Science, North Carolina State University, Raleigh, North Carolina 27695; and Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A8, CanadaCite this: J. Agric. Food Chem. 2004, 52, 10, 3209Publication Date (Web):April 20, 2004Publication History Received16 March 2004Published online20 April 2004Published inissue 1 May 2004https://pubs.acs.org/doi/10.1021/jf0401367https://doi.org/10.1021/jf0401367article-commentaryACS PublicationsCopyright © 2004 American Chemical Society. This publication is available under these Terms of Use. Request reuse permissions This publication is free to access through this site. Learn MoreArticle Views207Altmetric-Citations-LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail PDF (20 KB) Get e-AlertscloseSUBJECTS:Chromatography,Organic polymers,Peptides and proteins,Purification,Separation science Get e-Alerts}, number={10}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Fasina, YO and Swaisgood, HE and Garlich, JD and Classen, HL}, year={2004}, month={May}, pages={3209–3209} }
 @article{fasina_swaisgood_garlich_classen_2003, title={A semi-pilot-scale procedure for isolating and purifying soybean (Glycine max) lectin}, volume={51}, ISSN={["1520-5118"]}, DOI={10.1021/jf021125l}, abstractNote={Availability of gram quantities of purified soybean lectin (SBL) to scientists will foster discovery of novel biomedical applications of the lectin and provide the opportunity to investigate the antinutritional effects of SBL in soybean-consuming food animals and poultry. Therefore, a semi-pilot-scale procedure for isolating and purifying SBL was designed. Defatted soyflour was extracted overnight with 0.9% NaCl at 4 degrees C. The extract obtained was filtered (0.45 microm membrane) and subjected to affinity chromatography using a column containing N-acetyl-D-galactosamine resin that is specific for SBL. Bound SBL was eluted off the column with 0.14 M galactose solution. The eluent was ultrafiltered (30 kDa), and the resulting solution (SBL and water) was freeze-dried. Electrophoretic analysis and hemagglutination assay revealed that the freeze-dried SBL was similar to Sigma-grade SBL in purity and activity (35 and 33 HU/mg protein, respectively). The procedure yielded 141 mg of SBL/100 g of soyflour.}, number={16}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Fasina, YO and Swaisgood, HE and Garlich, JD and Classen, HL}, year={2003}, month={Jul}, pages={4532–4538} }
 @misc{clare_catignani_swaisgood_2003, title={Biodefense properties of milk: The role of antimicrobial proteins and peptides}, volume={9}, ISSN={["1873-4286"]}, DOI={10.2174/1381612033454874}, abstractNote={Mammary fluids, colostrum and milk, deliver nature's first host defense systems upon birth, and these essential liquids are critical for survival of the neonate. The identification and characterization of anti-infectious proteins were among the early scientific discoveries and this group of proteins has long been recognized for promoting health benefits in both newborns and adults. Among the more widely studied are the immunoglobulins, lactoperoxidase, lysozyme, and lactoferrin. Recently, it was shown that alpha--lactalbumin may also function in a protective capacity dependent upon its folding state. Some of these, especially lactoferrin, also display an immunomodulatory role in which case a totally separate cascade of host defense responses is initiated. It was noted that the mechanism of action for this cluster of sentry proteins does vary; thus, this protective strategy provides for a broad range of responsive reactions to infection. Presently, there is a major focus on the discovery of novel peptides that can be generated from existing milk proteins via proteolytic reactions. To date, this substrate list includes alpha--lactalbumin, beta-lactoglobulin, all casein fractions, and lactoferrin. Again, the immunoregulatory effects prompted as a result of the appearance of these peptides are currently being defined. Herein, we review the principal biological properties associated with each of these contributing milk components with a special emphasis on the role of biodefensive milk peptides. We envision future contributions emerging from this research field as an opportunity to develop effective new therapies to be used in treating infectious diseases and promoting health benefits in vivo.}, number={16}, journal={CURRENT PHARMACEUTICAL DESIGN}, author={Clare, DA and Catignani, GL and Swaisgood, HE}, year={2003}, pages={1239–1255} }
 @article{wang_swaisgood_shih_2003, title={Bioimmobilization of keratinase using Bacillus subtilis and Escherichia coli systems}, volume={81}, ISSN={["0006-3592"]}, DOI={10.1002/bit.10485}, abstractNote={Abstract}, number={4}, journal={BIOTECHNOLOGY AND BIOENGINEERING}, author={Wang, JJ and Swaisgood, HE and Shih, JCH}, year={2003}, month={Feb}, pages={421–429} }
 @article{fasina_classen_garlich_swaisgood_clare_2003, title={Investigating the possibility of monitoring lectin levels in commercial soybean meals intended for poultry feeding using steam-heated soybean meal as a model}, volume={82}, ISSN={["0032-5791"]}, DOI={10.1093/ps/82.4.648}, abstractNote={Native soybean lectins (SBL) could potentially have deleterious effects on young animals. The objectives of this study were to determine the optimum processing temperature and time at which SBL is inactivated and to investigate the possibility of using urease activity (UA) to predict residual lectin levels in soybean meal (SBM). Raw defatted SBM was steam-heated at incremental temperatures between 90 and 120 degrees C for 5 to 20 min in an autoclave. The processed meals were subjected to native-PAGE and measurement of total carbohydrate-binding lectin (TCBL), agglutinating lectin (AL), UA, and trypsin inhibitor (TI). Processing severity was evaluated by determining protein solubility in 0.2% potassium hydroxide. Results indicated that levels of all antinutrients (TCBL, AL, UA, and TI) decreased with increasing processing temperature (P < 0.05). The intensity of the lectin band on the electrophoresis gel was considerably reduced when meal was heated at 100 degrees C for 5 min. This result implied that lectin inactivation occurred at 100 degrees C. More than 90% of all the original antinutrient levels in the raw meal were destroyed when meals were heated at 100 degrees C for 5 min. Meals processed at 100 degrees C for 5 to 20 min had protein solubility values (80 to 85%) indicative of adequate processing. The denaturation pattern of UA was highly correlated with that of SBL (r > or = 0.73), indicating that UA could be used for monitoring lectin levels in commercial meals. We concluded that UA of 0.03 to 0.09 units of pH change are indicative of adequately processed meals that contain negligible lectin levels.}, number={4}, journal={POULTRY SCIENCE}, author={Fasina, YO and Classen, HL and Garlich, JD and Swaisgood, HE and Clare, DA}, year={2003}, month={Apr}, pages={648–656} }
 @article{wang_swaisgood_shih_2003, title={Production and characterization of bio-immobilized keratinase in proteolysis and keratinolysis}, volume={32}, ISSN={["0141-0229"]}, DOI={10.1016/S0141-0229(03)00060-7}, abstractNote={Extracellular production of keratinase–streptavidin fusion protein (KER–STP) was accomplished by the cloning of Bacillus subtilis with a transforming plasmid carrying the kerA-stp fusion gene. The fusion protein was readily immobilized onto a biotinylated solid matrix by mixing in the culture medium. The properties and reaction kinetics of free and immobilized keratinase (KE) were characterized and compared. Heat stability and pH tolerance were greatly improved by immobilization, but the catalytic efficiency (kcat/Km) was reduced by eightfold. The yield of bio-immobilization using bioselective adsorption of the fusion protein was approximately 20%, as estimated from the activity of free KE. HPLC analysis of reaction products demonstrated the hydrolysis of feather keratin, casein, and bovine serum albumin (BSA) by the immobilized KE. The rates of reactions are lower than those of the free enzyme. On the other hand, the stability of the enzyme was greatly improved.}, number={7}, journal={ENZYME AND MICROBIAL TECHNOLOGY}, author={Wang, JJ and Swaisgood, HE and Shih, JCH}, year={2003}, month={Jun}, pages={812–819} }
 @article{wilcox_clare_valentine_swaisgood_2002, title={Immobilization and utilization of the recombinant fusion proteins trypsin-streptavidin and streptavidin-transglutaminase for modification of whey protein isolate functionality}, volume={50}, ISSN={["1520-5118"]}, DOI={10.1021/jf011603c}, abstractNote={A method was developed for the production of a hydrolyzed/polymerized whey protein derivative with altered solution and gelation properties using a combination of recombinant DNA and immobilized enzyme technologies. The recombinant fusion proteins trypsin-streptavidin (TrypSA) and streptavidin-transglutaminase (cSAcTG) were produced in Escherichia coli, extracted, and then immobilized by selective adsorption on biotinylated controlled-pore glass. Recirculation through a TrypSA reactor induced limited proteolysis of whey proteins. Hydrolysates were then recirculated through a cSAcTG reactor for incremental periods of time to arrive at increasing degrees of polymerization. The polymers were subsequently analyzed for viscosity/flow behavior, gelation properties, and fracture properties using shear rate ramps/intrinsic viscosity, small-strain oscillatory rheology, and vane viscometry, respectively. By combining limited proteolysis with controlled cross-linking, it was possible to create derivatives of whey proteins with enhanced functional properties. Increases in the degree of whey protein modification were correlated with greater apparent viscosity and intrinsic viscosity, lowered gel point temperatures, and stronger, more brittle gels. This method allowed for recycling of the enzyme, eliminated the requirement for a downstream inactivation step, and permitted control over the extent of modification. Utilization of a similar process may allow for the production of designer proteins engineered with specific functionalities.}, number={13}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Wilcox, CP and Clare, DA and Valentine, VW and Swaisgood, HE}, year={2002}, month={Jun}, pages={3723–3730} }
 @article{wilcox_janolino_swaisgood_2002, title={Isolation and partial characterization of CD36 from skim milk}, volume={85}, ISSN={["0022-0302"]}, DOI={10.3168/jds.S0022-0302(02)74265-3}, abstractNote={CD36, a common milk fat globule membrane glycoprotein, was isolated from skim milk by methods similar to those previously utilized for the isolation of sulfhydryl oxidase. Two separate methods that were employed, gave similar purity as observed by electrophoresis. The first was based on differential centrifugation and size-exclusion chromatography, whereas the second combined ultrafiltration and affinity chromatography. After significant purification, the protein was identified by Western blotting and sequence analysis. Deglycosylation decreased the apparent molecular mass from approximately 85 to 57 kDa. These results suggested tissue-specific glycosylation. The purified fractions also exhibited low levels of sulfhydryl oxidase activity, the significance of which will require further study.}, number={8}, journal={JOURNAL OF DAIRY SCIENCE}, author={Wilcox, CP and Janolino, VG and Swaisgood, HE}, year={2002}, month={Aug}, pages={1903–1908} }
 @article{wilcox_swaisgood_2002, title={Modification of the rheological properties of whey protein isolate through the use of an immobilized microbial transglutaminase}, volume={50}, ISSN={["1520-5118"]}, DOI={10.1021/jf0117154}, abstractNote={A process was developed in which calcium-independent, microbial transglutaminase (mTgase) was immobilized to controlled-pore glass. Avidin was adsorbed to glass beads that had been derivatized and biotinylated. The enzyme was biotinylated and adsorbed to the avidin affinity matrix. Solutions of 8% whey protein isolate (WPI) were then incubated with the mTgase beads, resulting in limited cross-linking of whey proteins. As incubation time increased, intrinsic viscosity increased, gelation temperature decreased, and stronger, more brittle gels were formed upon heating. This process allowed for recycling of the enzyme, eliminated the requirement for a downstream inactivation step, and permitted control over the extent of cross-linking. The functional properties of several batches of WPI were modified using <10 mg of the same enzyme, illustrating the capacity of immobilized enzymes to be used more frequently in applications of this nature.}, number={20}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Wilcox, CP and Swaisgood, HE}, year={2002}, month={Sep}, pages={5546–5551} }
 @article{zhao_clare_catignani_swaisgood_2002, title={Purification and characterization of the fusion protein trypsin-streptavidin expressed in Escherichia coli}, volume={21}, ISSN={["0277-8033"]}, DOI={10.1023/A:1021134617137}, abstractNote={Expression of fusion protein trypsin-streptavidin (TRYPSA) in Escherichia coli was evaluated and the protein purified. Protein expression was induced by 1 mM isopropylthio-beta-D-galactoside (IPTG), and the enzyme activity was measured by the hydrolysis rate of p-toluenesulfonyl-L-arginine methyl ester (TAME). Expression of the fusion protein in the cell-free extract decreased with increased induction time; correspondingly, that in the inclusion bodies increased. The total expression in Luria-Bertani broth (LB) and Terrific Broth (TB) media reached the highest levels in 2 hr at 30 degrees C. The optimum expression level was 35 and 48 U/L in LB and TB, respectively. Expression of the fusion protein was verified by Western Blot analysis using streptavidin antiserum, and the fusion protein was purified using a benzamidine Sepharose 6B affinity column at room temperature. The molecular size of the soluble purified fusion protein was determined by size-exclusion chromatography using Superose 12 FPLC. A molecular weight of 39-40 kDa was obtained, indicating that the soluble protein exists as a monomer; thus, the presence of the trypsin domain must prevent the streptavidin domain from tetramer formation.}, number={6}, journal={JOURNAL OF PROTEIN CHEMISTRY}, author={Zhao, F and Clare, DA and Catignani, GL and Swaisgood, HE}, year={2002}, month={Aug}, pages={413–418} }
 @article{janolino_swaisgood_2002, title={Trypsin imobilization on derivatized cellulose beads by biospecific avidin-biotin interaction and characterization of the immobilized activity}, volume={26}, DOI={10.1111/j.1745-4514.2002.tb00869.x}, abstractNote={Trypsin was immobilized on cellulose beads using the biospecific and high affinity avidin-biotin interaction. Trypsin and cellulose beads were biotinylated with sulfosuccinimidyl-6-(biotinamido) hexanoate (NHS-LC-biotin). Avidin and biotinylated trypsin were sequentially adsorbed to the biotinylated cellulose beads. A similar procedure was carried out using controlled-pore glass (CPG) beads. The properties of the two trypsin bioreactors were examined and compared. The substrate used for the assay of trypsin activity was p-tosyl-L-arginine methyl ester and the extent of biotinylation of biotinylated trypsin and of immobilized biotin on cellulose beads and on CPG beads were determined using the 2-[4'-hydroxyazobenzene]benzoic acid dye-binding method. Biotinylated trypsin in solution retained about 82% of the specific activity of native trypsin. Cellulose beads contained 0.184 μmol/mL (1.15 μmol/g) biotin and CPG beads, 0.329 μmol/mL (0.987 μmol/g). After regeneration, the biotin contents became slightly lower, namely, 0.159 μmol/mL for cellulose beads and 0.315 μmol/mL for CPG beads. The specific activities of trypsin immobilized on cellulose beads and CPG beads were 32 U/mL (202 U/g) and 43 U/mL (130 U/g), respectively. These studies indicate that cellulose beads can be biotinylated for use as bioselective support. Cette etude utilise l'interaction avidine-biotine comme modele pour l'adsorption selective et l'immobilisation de proteines de fusion enzyme-streptavidine recombinantes pour la preparation de bioreacteur. L'application de cette technologie permet de realiser la purification et l'immobilisation dans une seule etape. Cette etude caracterise enfin la trypsine immobilisee par cette methode en comparaison avec celle immobilisee sur des billes de verre.}, number={2}, journal={Journal of Food Biochemistry}, author={Janolino, V. G. and Swaisgood, H. E.}, year={2002}, pages={119–129} }
 @article{vardhanabhuti_foegeding_mcguffey_daubert_swaisgood_2001, title={Gelation properties of dispersions containing polymerized and native whey protein isolate}, volume={15}, ISSN={["1873-7137"]}, DOI={10.1016/S0268-005X(00)00062-X}, abstractNote={Whey protein polymers (WP-polymers) were prepared by heating whey protein isolate below the critical concentration for gelation at neutral pH and low salt conditions. The effects of WP-polymers and salt types (CaCl2 or NaCl) on rheological properties (large-strain and small-strain analysis), water holding properties, turbidity and microstructure of heat-induced whey protein isolate gels were investigated. Replacement of native whey protein isolate with WP-polymers increased fracture stress, fracture modulus, held water, and the translucency of gels. With both salt types, the addition of WP-polymers changed the gel structure from particulate to fine-stranded. However, the effect of WP-polymers on rheological properties was salt specific. Addition of 20–100% WP-polymers in the presence of 10 mM CaCl2 caused a continued increase in fracture stress. In contrast, protein dispersions containing 30 mM NaCl did not form self-supporting gels when ≥60% WP-polymers were added. Dispersions containing 200 mM NaCl formed self supporting gels at all levels of WP-polymer addition but fracture stresses for gels containing 20–100% WP were similar. Dispersions containing 80% WP-polymers and 200 mM NaCl had lower gel points (time and temperature) than dispersions with 80% WP-polymers and 10 mM CaCl2. It appeared that CaCl2 was more effective in increasing gel fracture stress while NaCl was more effective in decreasing gelation time. Different gel properties may be prepared by altering the amount of WP-polymers and salt types.}, number={2}, journal={FOOD HYDROCOLLOIDS}, author={Vardhanabhuti, B and Foegeding, EA and McGuffey, MK and Daubert, CR and Swaisgood, HE}, year={2001}, month={Mar}, pages={165–175} }
 @article{gurgel_carbonell_swaisgood_2001, title={Identification of peptide ligands generated by combinatorial chemistry that bind alpha-lactalbumin}, volume={36}, ISSN={["0149-6395"]}, DOI={10.1081/SS-100106100}, abstractNote={α-Lactalbumin is a whey protein with high digestibility and low potential for causing allergic problems in infants, making it a strong candidate for use in infant formulas. The development of an efficient and scalable process for isolation of α-lactalbumin is necessary to allow its use on a large scale. Affinity chromatography using short peptides as ligands is a promising technique because it allows the recovery of specific proteins without the use of harsh chemicals or problems due to ligand release. In the present paper we describe the identification of the hexapeptide WHWRKR, obtained from a combinatorial library, that shows affinity for α-lactalbumin.}, number={11}, journal={SEPARATION SCIENCE AND TECHNOLOGY}, author={Gurgel, PV and Carbonell, RG and Swaisgood, HE}, year={2001}, pages={2411–2431} }
 @article{clare_valentine_catignani_swaisgood_2001, title={Molecular design, expression, and affinity immobilization of a trypsin-streptavidin fusion protein}, volume={28}, ISSN={["1879-0909"]}, DOI={10.1016/S0141-0229(00)00361-6}, abstractNote={A trypsin-streptavidin (TRYPSA) fusion protein was designed and its expression in Escherichia coli was evaluated. The streptavidin gene was PCR modified and cloned into the pET expression vector. The trypsin gene was subsequently inserted into this plasmid, thus generating a colinear fusion of trypsin and streptavidin genes (pTRYPSA). This engineering strategy was verified, and TRYPSA was expressed after IPTG induction using the E. coli strains, BL21(DE3) and BL21(DE3)pLysS. Standard protein fractions of the cell lysate were prepared and trypsin activity was primarily detected in the periplasmic and inclusion body fractions. Immunoblotting showed a single Western-positive band exhibiting a molecular weight of 39,000 Da. A biotinylated porous glass affinity matrix was prepared and selective adsorption resulted in a one-step purification and immobilization of TRYPSA from crude cell lysate. Trypsin activity was verified using a synthetic substrate. This enzyme bioreactor should serve as an excellent prototype for future studies that will examine the effect of limited proteolysis on functional characteristics of milk proteins, including gelling, emulsifying and foaming properties.}, number={6}, journal={ENZYME AND MICROBIAL TECHNOLOGY}, author={Clare, DA and Valentine, VW and Catignani, GL and Swaisgood, HE}, year={2001}, month={Apr}, pages={483–491} }
 @misc{swaisgood_wang_allen_2001, title={Protein ingredient for carrying lipophilic nutrients}, volume={6,290,974}, number={2001 Sept. 18}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Swaisgood, H. E. and Wang, Q.-W. and Allen, J. C.}, year={2001} }
 @article{gurgel_carbonell_swaisgood_2001, title={Studies of the binding of alpha-lactalbumin to immobilized peptide ligands}, volume={49}, ISSN={["1520-5118"]}, DOI={10.1021/jf010462b}, abstractNote={The present work investigates the mechanism of binding of α-lactalbumin to the peptide ligand WHWRKR and its variants HWRKR and acetylated WHWRKR immobilized on a polymethacrylate chromatographic resin. The presence of two temperature-dependent binding mechanisms and one temperature-independent mechanism was demonstrated. Injections of different forms of α-lactalbumin (apo-α-lactalbumin, D87A mutant α-lactalbumin) displayed similar behaviors when compared to native α-lactalbumin, while lysozyme showed little or no binding to the WHWRKR and AcWHWRKR resins. An alternative process for isolation of α-lactalbumin from WPI was shown, using consecutive injections of WPI with limited elution. Keywords: α-Lactalbumin; peptide ligands; bioselective adsorption; binding mechanism}, number={12}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Gurgel, PV and Carbonell, RG and Swaisgood, HE}, year={2001}, month={Dec}, pages={5765–5770} }
 @misc{clare_swaisgood_2000, title={Bioactive milk peptides: A prospectus}, volume={83}, ISSN={["1525-3198"]}, DOI={10.3168/jds.S0022-0302(00)74983-6}, abstractNote={Bioactive peptides have been identified within the amino acid sequences of native milk proteins. Hydrolytic reactions, such as those catalyzed by digestive enzymes, result in their release. These peptides directly influence numerous biological processes evoking behavioral, gastrointestinal, hormonal, immunological, neurological, and nutritional responses. The specific bioreactions associated with each physiological class have been well characterized. Herein, we review the scientific literature and attempt to stimulate consideration of the continued use of bioactive peptides and their expanded development as a commercial product. Several applications have already evolved. For example, phosphopeptides derived from casein fractions are currently used as both dietary and pharmaceutical supplements. Potentially, the addition of bioactive peptides to food products could improve consumer safety as a result of their antimicrobial properties. Lastly, bioactive peptides may function as health care products, providing therapeutic value for either treatment of infection or prevention of disease.}, number={6}, journal={JOURNAL OF DAIRY SCIENCE}, author={Clare, DA and Swaisgood, HE}, year={2000}, month={Jun}, pages={1187–1195} }
 @article{gurgel_carbonell_swaisgood_2000, title={Fractionation of whey proteins with a hexapeptide ligand affinity resin}, volume={9}, ISSN={["0923-179X"]}, DOI={10.1023/A:1011191818927}, abstractNote={The isolation of individual proteins from whey would allow production of more consistent and reliable products by the food industry and possibly would also increase their use in the pharmaceutical industry. Alpha-lactalbumin is the second most prevalent protein in bovine milk whey and has many uses including serving as an excellent protein source in infant formulas, power drinks and other beverages that require soluble, nutritional protein. In this study, we describe two methods for production of alpha-lactalbumin from whey protein isolate using bioselective adsorption. The use of a peptide ligand (WHWRKR) attached to a resin allowed production of an alpha-lactalbumin-rich fraction with a purity of 90.6% and a recovery of 47.9%, while also producing other fractions of commercial interest. The combined use of an amino resin followed by the WHWRKR resin produce a highly purified alpha-lactalbumin (100%) with a yield of 35.2%.}, number={6}, journal={BIOSEPARATION}, author={Gurgel, PV and Carbonell, RG and Swaisgood, HE}, year={2000}, pages={385–392} }
 @article{brumano_rogana_swaisgood_2000, title={Thermodynamics of unfolding of beta-trypsin at pH 2.8}, volume={382}, DOI={10.1006/abbi.2000.1983}, abstractNote={Abstract The unfolding equilibrium of β-trypsin induced by thermal and chemical denaturation was thermodynamically characterized. Thermal unfolding equilibria were monitored using UV absorption and both far- and near-UV CD spectroscopy, while fluorescence was used to monitor urea-induced transitions. Thermal and urea transition curves are reversible and cooperative and both sets of data can be reasonably fitted using a two-state model for the unfolding of this protein. Plots of the fraction denatured, calculated from thermal denaturation curves at different wavelengths, versus temperature are coincident. In addition, the ratio of the enthalpy of denaturation obtained by scanning calorimetry to the van't Hoff enthalpy is close to unity, which supports the two-state model. Considering the differences in experimental approaches, the value for the stability of β-trypsin estimated from spectroscopic data (Δ G u = 6.0 ± 0.2 kcal/mol) is in reasonable agreement with the value calculated from urea titration curves (Δ G u H 2 O = 5.5 ± 0.3 kcal/mol) at pH 2.8 and 300°K.}, number={1}, journal={Archives of Biochemistry and Biophysics}, author={Brumano, M. H. N. and Rogana, E. and Swaisgood, H. E.}, year={2000}, pages={57–62} }
 @article{wang_allen_swaisgood_1999, title={Binding of lipophilic nutrients to beta-lactoglobulin prepared by bioselective adsorption}, volume={82}, ISSN={["0022-0302"]}, DOI={10.3168/jds.S0022-0302(99)75231-8}, abstractNote={The binding of the lipophilic nutrients, retinal, vitamin D2, and retinyl palmitate by beta-lactoglobulin was measured by analysis of changes in the fluorescence of the tryptophanyl residue of beta-lactoglobulin or the retinyl moiety. The fluorescence intensity of the tryptophanyl residue was quenched by retinoid or vitamin D binding but was enhanced by palmitate binding. The analysis of competitive binding experiments with palmitate indicated that retinal and palmitate did not compete for the same site; however, vitamin D2, which binds with a stoichiometry of 2, appeared to displace palmitate at higher concentrations. Also, the retinoids and vitamin D2 were bound more tightly than was palmitate. The results are consistent with the model in which the retinoids and vitamin D2 bind in the calyx formed by the beta-barrel; palmitate and a second molecule of vitamin D2 bind in a surface pocket near the dimer contact region. Retinyl palmitate, which has both moieties, appeared to bind at both sites.}, number={2}, journal={JOURNAL OF DAIRY SCIENCE}, author={Wang, QW and Allen, JC and Swaisgood, HE}, year={1999}, month={Feb}, pages={257–264} }
 @article{huang_catignani_swaisgood_1999, title={Modification of rheological properties of whey protein isolates by limited proteolysis}, volume={43}, ISSN={["0027-769X"]}, DOI={10.1002/(SICI)1521-3803(19990301)43:2<79::AID-FOOD79>3.0.CO;2-8}, abstractNote={Whey protein isolate (WPI) was subjected to limited tryptic hydrolysis and the effect of the limited hydrolysis on the rheological properties of WPI was examined and compared with those of untreated WPI. At 10% concentration (w/v in 50 mM TES buffer, pH 7.0, containing 50 mM NaCI), both WPI and the enzyme-treated WPI (EWPI) formed heat-induced viscoelastic gels. However, EWPI formed weaker gels (lower storage modulus) than WPI gels. Moreover, a lower gelation point (77 °C) was obtained for EWPI as compared with that of WPI which gelled at 80 °C only after holding 1.4 min. Thermal analysis and aggregation studies indicated that limited proteolysis resulted in changes in the denaturation and aggregation properties. As a consequenece, EWPI formed particulated gels, while WPI formed fine-stranded gels. In keeping with the formation ofa particulate gel, Texture Profile Analysis (TPA) ofthe heat-induced gels (at 80 °C for 30 min) revealed that EWPI gels possessed significantly higher (p < 0.05) cohesiveness, hardness, gumminess, and chewiness but did not fracture at 75% deformation. The results suggest that the domain peptides, especially β-lactoglobulin domains released by the limited proteolysis, were responsible for the altered gelation properties.}, number={2}, journal={NAHRUNG-FOOD}, author={Huang, XL and Catignani, GL and Swaisgood, HE}, year={1999}, month={Apr}, pages={79–85} }
 @article{park_swaisgood_allen_1998, title={Calcium binding of phosphopeptides derived from hydrolysis of alpha(s)-Casein or beta-Casein using immobilized trypsin}, volume={81}, ISSN={["0022-0302"]}, DOI={10.3168/jds.S0022-0302(98)75844-8}, abstractNote={Abstract Calcium binding to casein phosphopeptides that were derived from α s -CN or β -CN was studied. Purified α s -CN or β -CN was prepared from fresh skim milk using an anion-exchange column. Peptides were prepared by casein hydrolysis using a fluidized bed bioreactor containing 2ml of immobilized trypsin (activity: 49.4 U/g of beads). The disappearance of intact protein and the appearance of products of low molecular mass were monitored by SDS-PAGE. α s -Casein and β -CN hydrolysates were loaded on an anion-exchange column, followed by stepwise elution with 0, 0.1, 0.2, 0.4, and 0.5 M KCl in equilibration buffer to separate the phosphopeptides from the other casein peptides. Protein and P were measured in the elution peaks. Calcium binding to each fraction was determined with a Ca-selective electrode. Electrophoresis showed that intact proteins were hydrolyzed rapidly, and peptides appeared on the gel in greater concentrations as the incubation time increased. The major products were a main band with a molecular mass of 6.2 kDa from β -CN hydrolysates and a series of bands from 4.0 to 12.8 kDa from a α s -CN hydrolysate. The greatest yield and concentration of phosphate from β -CN hydrolysate were found in the peak that eluted with 0.4 M KCl in equilibration buffer and for α s -CN in the peak that eluted with 0.1 M KCl. The α s -CN phosphopeptides showed greater Ca 2+ binding than the phosphopeptides from β -CN. Separation of casein phosphopeptides using anion exchange was not specific. However, results showed that each peak containing high concentrations of phosphate had Ca 2+ -binding ability. Further characterization of these casein phosphopeptides might result in a Ca-complexing food ingredient.}, number={11}, journal={JOURNAL OF DAIRY SCIENCE}, author={Park, O and Swaisgood, HE and Allen, JC}, year={1998}, month={Nov}, pages={2850–2857} }
 @article{lee_swaisgood_1998, title={Cloning and expression of a streptavidin-lipase fusion gene in Escherichia coli and characterization of the immobilized fusion protein}, volume={22}, ISSN={["1879-0909"]}, DOI={10.1016/S0141-0229(97)00174-9}, abstractNote={A gene for a streptavidin-lipase fusion protein was constructed by cloning a PCR-modified Pseudomonas fluorescens B52 lipase gene into a streptavidin chimeric protein expression vector, pStp4. The plasmids, pSTLP1 or pSTLP2, were used to transform Escherichia coli NM522 or DH5α. Plasmid pSTLP2, which contains a laclq gene upstream from the promoter, gave better expression of the bifunctional fusion protein when the cells were induced. Correct insertion of the fused gene was confirmed by DNA sequencing of the linker region and the lipase gene, by identification of a protein band of the correct molecular size (66 kDa) on SDS-PAGE, and by Western blot analysis using antistreptavidin antibody. Streptavidin-lipase fusion protein was purified and immobilized in a single step from recombinant cell lysates by bioselective adsorption on 6-(biotinamido)hexanamidopropyl-controlled pore glass. The hydrolytic activity of the resulting immobilized enzyme exhibited a pH optimum between 7 and 8 and a preference for short-chain fatty acids. Comparison of the hydrolytic activity of immobilized B52 lipase with that of commercial SAM-2 lipase from P. fluorescens suggests that about 30% of the activity was retained upon immobilization. Transesterification of tricaprylin with oleic acid in hexane by immobilized lipase indicated that 11% of the reaction products were derived from transesterification.}, number={4}, journal={ENZYME AND MICROBIAL TECHNOLOGY}, author={Lee, P and Swaisgood, HE}, year={1998}, month={Mar}, pages={246–254} }
 @article{koo_foegeding_swaisgood_1998, title={Construction and expression of a bifunctional single-chain antibody against Bacillus cereus spores}, volume={64}, number={7}, journal={Applied and Environmental Microbiology}, author={Koo, K. and Foegeding, P. M. and Swaisgood, H. E.}, year={1998}, pages={2490–2496} }
 @article{koo_foegeding_swaisgood_1998, title={Development of a streptavidin-conjugated single-chain antibody that binds Bacillus cereus spores}, volume={64}, number={7}, journal={Applied and Environmental Microbiology}, author={Koo, K. and Foegeding, P. M. and Swaisgood, H. E.}, year={1998}, pages={2497–2502} }
 @article{koo_foegeding_swaisgood_1998, title={Isolation of RNA and DNA fragments using diatomaceous earth}, volume={12}, ISSN={["0951-208X"]}, DOI={10.1023/A:1008859632378}, number={7}, journal={BIOTECHNOLOGY TECHNIQUES}, author={Koo, K and Foegeding, PM and Swaisgood, HE}, year={1998}, month={Jul}, pages={549–552} }
 @article{wang_allen_swaisgood_1998, title={Protein concentration dependence of palmitate binding to beta-lactoglobulin}, volume={81}, ISSN={["1525-3198"]}, DOI={10.3168/jds.S0022-0302(98)75553-5}, abstractNote={Abstract The binding of palmitate to β -lactoglobulin at protein concentrations ranging from 1 to 200 μM was determined using an ultrafiltration method with [ 14 C]palmitate. Fit of the data to theoretical models required the assumption of two independent sets of binding sites; however, binding characteristics were dependent on the protein concentration. A model assuming one set of sites on the protein monomer and another on the dimer was consistent with the data. The analysis suggests that 2mol of palmitate are bound/mol of dimer and that the binding constant is of the order of 10 5 M –1 ; a larger number of palmitate molecules are bound per mole of monomer with a smaller binding constant of the order of 10 4 M –1 . Apparently, formation of the dimer, by hydrophobic interactions at the monomer contact site, eliminated palmitate binding sites on the monomer but formed a higher affinity pocket for binding to the dimer.}, number={1}, journal={JOURNAL OF DAIRY SCIENCE}, author={Wang, QWQ and Allen, JC and Swaisgood, HE}, year={1998}, month={Jan}, pages={76–81} }
 @article{wang_allen_swaisgood_1997, title={Binding of retinoids to beta-lactoglobulin isolated by bioselective adsorption}, volume={80}, ISSN={["0022-0302"]}, DOI={10.3168/jds.S0022-0302(97)76029-6}, abstractNote={Abstract Binding of the retinoids, all-trans -retinol, all- trans -retinal, all-trans -retinyl acetate, and all-trans -retinoic acid, to β-lactoglobulin (LG) (96% purity) that had been prepared by bioselective adsorption on N-retinyl-Celite TM was determined from changes in the fluorescence quenching (332nm) of the protein tryptophanyl residues. High affinity binding of all of these compounds occurred at pH 7.0, and the apparent dissociation constant ranged from 1.7 to 3.6 × 10 –8 M . Furthermore, a stoichiometry of 1.0 mol·mol –1 of protein was obtained for each case, indicating that all of the sites in the protein preparation were available. When β-LG in whey protein isolate (57.4% β-LG) was studied, a stoichiometry of 0.65 to 0.82 mol·mol –1 of protein was obtained, indicating that a large number of the sites already had bound lipid or that the protein had been denatured. As the pH was lowered toward 5.15, the affinity decreased about fourfold, but the stoichiometry of binding was unchanged. Far UV circular dichroism spectra indicated that the secondary structure of the protein was not significantly affected by ligand binding; however, the near UV spectra were changed, indicating that the flexibility of tryptophanyl residues decreased. The latter effect is consistent with the change in fluorescence quenching and suggests that a tryptophan is in the binding site.}, number={6}, journal={JOURNAL OF DAIRY SCIENCE}, author={Wang, QW and Allen, JC and Swaisgood, HE}, year={1997}, month={Jun}, pages={1047–1053} }
 @article{wang_allen_swaisgood_1997, title={Binding of vitamin D and cholesterol to beta-lactoglobulin}, volume={80}, ISSN={["0022-0302"]}, DOI={10.3168/jds.S0022-0302(97)76030-2}, abstractNote={Abstract β -Lactoglobulin was isolated directly from acidic whey by bioselective adsorption on N-retinyl-Celite TM , yielding preparations of ≥96% purity. Interactions of these preparations with vitamin D 2 , vitamin D 3 , ergosterol, cholesterol, and 7-dehydrocholesterol were examined by following changes in the fluorescence spectra. Both the excitation and emission spectra indicated that energy was transferred between the tryptophanyl residues of the protein and the chromophore of the ligand. Analyses of the fluorescence changes that occurred upon titration of β -LG with the various ligands allowed determination of the dissociation constant for the complex and the number of moles bound per mole of protein. The affinity for vitamin D 2 (dissociation constant of 4.91 n M ) was 10-fold higher than that of the other compounds, except for ergosterol, which was 5-fold larger than the others. Also, the affinity was 10-fold higher than that typically reported for the retinoids. Furthermore, the value obtained for the number of moles bound per mole of protein was 2 mol·mol –1 for each of the ligands examined in this study; it has been well established that all of the retinoids are bound with a stoichiometry of 1.0. These results suggest that β -LG may be a better carrier of vitamin D than of vitamin A.}, number={6}, journal={JOURNAL OF DAIRY SCIENCE}, author={Wang, QW and Allen, JC and Swaisgood, HE}, year={1997}, month={Jun}, pages={1054–1059} }
 @article{lee_swaisgood_1997, title={Characterization of a chemically conjugated lipase bioreactor}, volume={45}, ISSN={["0021-8561"]}, DOI={10.1021/jf970167k}, abstractNote={Lipase from Candida cylindracea was immobilized on glass beads using the biospecific and high-affinity avidin−biotin interaction. Biotinylated lipase and glass beads were prepared by reactions of lipase and 3-aminopropyl glass beads with sulfosuccinimidyl-6-(biotinamido)hexanoate (NHS-LC-biotin). Avidin and biotinylated lipase were sequentially adsorbed to the biotinylated glass beads. Biotinylated lipase in solution retained about 63% of the hydrolytic specific activity of native lipase when an average 3 mol of biotin was incorporated/mol of lipase. Nonporous glass beads contained more biotin and protein (avidin and lipase) per unit of surface area, followed by 302 nm mean pore diameter controlled-pore glass beads (CPG-3000) and 198 nm mean pore diameter controlled-pore glass beads (CPG-2000). The hydrolytic specific activity of lipase immobilized on CPG-3000 and on nonporous beads was essentially the same as that for the biotinylated free enzyme, whereas that immobilized on CPG-2000 was about 50% less. ...}, number={8}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Lee, P and Swaisgood, HE}, year={1997}, month={Aug}, pages={3350–3356} }
 @article{huang_catignani_swaisgood_1997, title={Comparison of the properties of trypsin immobilized on 2 Celite(TM) derivatives}, volume={53}, ISSN={["0168-1656"]}, DOI={10.1016/S0168-1656(96)01656-2}, abstractNote={Trypsin was immobilized on 2 Celite derivatives and the kinetic properties of trypsin immobilized on these derivatives were determined and compared. Celite was derivatized with organosilane to give aminopropyl-Celite (APC) and a portion of this derivative was then succinylated to give succinamidopropyl-Celite (SAPC). Trypsin was covalently immobilized on APC using glutaraldehyde to activate amino groups and on SAPC using water-soluble carbodiimide to activate surface carboxyl groups. Enzyme loadings were 13.9 and 17.8 mg ml-1 of beads on APC and SAPC, respectively. Using p-tosyl-L-arginine methyl ester as substrate, the catalyst specific activity, KMapp and kcat/KMapp were 17.8 U ml-1 of beads, 3.60 and 21.0 mM-1 min-1, respectively, for trypsin-APC as compared with 24.5 U ml-1 of beads, 3.77 and 20.3 mM-1 min-1, respectively, for trypsin-SAPC. With beta-lactoglobulin as substrate, KMapp and kcat/KMapp were 0.36 and 1.62 mM-1 min-1 for trypsin-APC and 0.54 and 1.39 mM-1 min-1 for trypsin-SAPC, respectively. The pH range for optimal activity was much larger for both immobilized forms as compared with the soluble enzyme. The optimal temperature ranges were 40-50 degrees C for trypsin-APC and 50-60 degrees C for trypsin-SAPC. The two methods of immobilization on Celite gave biocataysts with similar kinetic properties but immobilization on SAPC yielded slightly higher loadings and higher specific activities.}, number={1}, journal={JOURNAL OF BIOTECHNOLOGY}, author={Huang, XL and Catignani, GL and Swaisgood, HE}, year={1997}, month={Feb}, pages={21–27} }
 @article{darquea_swaisgood_foegeding_1997, title={Development and characterization of a bioselective adsorption matrix for removal of Bacillus cereus spores from buffer and milk}, volume={30}, DOI={10.1006/fstl.1997.0266}, abstractNote={Bioselective adsorption was evaluated as a possible technology for food processing to enhance safety usingBacillus cereusin milk as a model system. Cataphote™ Microbeads class −400 were derivatized by attaching 3-aminopropyl groups (2.7 nm2/molecule) onto the surface of the bead. Carbohydrates on the Fc region of monoclonal antibody 183 againstB. cereusT spores were oxidized with potassium meta-periodate to allow for an oriented antibody immobilization (270 nm2/molecule). The adsorption matrix was characterized for its ability to bindB. cereusspores in comparison to a control matrix containing immobilized bovine serum albumin. When 2.5 × 106spores in skim milk were added to 1 mL of each matrix, the IgG-matrix was capable of removing 96% of that amount, 70% of which were bound with high affinity and were only eluted with 0.1 mol/L acetic acid. In contrast, the control matrix removed 90% of the spores added but only 7% were retained after washing the matrix. In addition, the IgG-matrix showed an excellent regeneration ability; the binding level did not decrease significantly after 28 trials with buffer or milk. Calculations determined that the bioadsorbant was capable of removing 8 × 106spores/m2. Thus, bioselective adsorption has promise as a technology to enhance safety of liquid foods or to improve analytical methodology.}, number={8}, journal={Food Science & Technology = Lebensmittel-Wissenschaft & -Technologie}, author={Darquea, D. and Swaisgood, H. E. and Foegeding, P. M.}, year={1997}, pages={786–792} }
 @article{huang_catignani_swaisgood_1997, title={Micro-scale method for determining foaming properties of protein}, volume={62}, ISSN={["0022-1147"]}, DOI={10.1111/j.1365-2621.1997.tb15030.x}, abstractNote={ABSTRACT}, number={5}, journal={JOURNAL OF FOOD SCIENCE}, author={Huang, XL and Catignani, GL and Swaisgood, HE}, year={1997}, pages={1028-&} }
 @article{lee_swaisgood_1997, title={Modification of milkfat physical properties by immobilized Pseudomonas fluorescens lipase}, volume={45}, ISSN={["0021-8561"]}, DOI={10.1021/jf970166s}, abstractNote={A bifunctional fusion protein was constructed by fusion of the streptavidin gene from Streptomyces avidinii to the lipase gene from Pseudomonas fluorescens, and the resulting streptavidin−lipase was expressed in Escherichia coli. Immobilized streptavidin−lipase was prepared by direct bioselective adsorption from crude cell lysates on biotinylated controlled-pore glass and used to catalyze interesterification of anhydrous butteroil. Changes in the triacylglycerol composition indicated that those with equivalent carbon numbers (ECN) ranging from 36 to 42 decreased, while those with ECN values from 48 to 50 increased following interesterification for 120 h in hexane at 42 °C. Both the melting temperatures and the solid fat content at various temperatures were lower as compared to those of the unmodified butteroil. Addition of unsaturated fatty acids, linoleic and linolenic, yielded modified butteroils with lower melting points and solid fat content, whereas addition of saturated fatty acids, palmitic and ste...}, number={8}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Lee, P and Swaisgood, HE}, year={1997}, month={Aug}, pages={3343–3349} }
 @article{wilcox_weissinger_long_fitzmaurice_mirkov_swaisgood_1997, title={Production and purification of an active bovine lysozyme in tobacco (Nicotiana tabacum): Utilization of value-added crop plants traditionally grown under intensive agriculture}, volume={45}, ISSN={["0021-8561"]}, DOI={10.1021/jf970156r}, abstractNote={The goals of this study were to express bovine lysozyme in tobacco and to purify the protein with a scaleable process to >90% homogeneity while retaining antimicrobial characteristics. Results showed that the enzyme was expressed at levels equivalent to 1−1.5% of total fraction 2 protein in each of five different transformant groups. The enzyme was subsequently purified to 93% homogeneity using an easily scaleable process while retaining high activity. It was concluded that tobacco was an excellent choice for expression of the recombinant protein and that the purification process developed in this study demonstrates methodology for isolation of high-value enzymes from tobacco and other crop plants. Keywords: Transgenic; lysozyme; recombinant protein; antimicrobial; Nicotiana tabacum}, number={7}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Wilcox, CP and Weissinger, AK and Long, RC and Fitzmaurice, LC and Mirkov, TE and Swaisgood, HE}, year={1997}, month={Jul}, pages={2793–2797} }
 @article{heddleson_allen_wang_swaisgood_1997, title={Purity and yield of beta-lactoglobulin isolated by an N-retinyl-Celite bioaffinity column}, volume={45}, ISSN={["0021-8561"]}, DOI={10.1021/jf9605198}, abstractNote={A bioaffinity column of all-trans-retinal immobilized on Celite was capable of isolating high-purity (94.5%) β-lactoglobulin from bovine acid whey. Conditions for producing a potentially hypoallergenic reduced β-lactoglobulin whey were investigated. Reapplication of pH 5.1 eluate to the column resulted in a final purity of 87% α-lactalbumin. The purity of β-lactoglobulin was slightly lower upon elution with buffers containing <0.4 M sodium phosphate, whereas the yield from desorbing buffers <0.1 M decreased to approximately 40% of that obtained with 0.4 M sodium phosphate. Desorption with low phosphate concentration was improved when pH was increased, suggesting that desorption involves titration of a protophilic group on β-lactoglobulin. These findings suggest that the retinal matrix shows promise in its application for creating hypoallergenic products and the isolation of high-purity β-lactoglobulin with useful functional properties. Keywords: β-Lactoglobulin; α-lactalbumin; bioselective adsorption; N-r...}, number={7}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Heddleson, RA and Allen, JC and Wang, QW and Swaisgood, HE}, year={1997}, month={Jul}, pages={2369–2373} }
 @misc{swaisgood_walsh_1994, title={Method of removing contaminants from a contact lens using electroblotting}, volume={5,292,372}, number={1994 March 8}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Swaisgood, H. E. and Walsh, M.}, year={1994} }
 @article{swaisgood_1993, title={REVIEW AND UPDATE OF CASEIN CHEMISTRY}, volume={76}, ISSN={["1525-3198"]}, DOI={10.3168/jds.S0022-0302(93)77645-6}, abstractNote={Of all food proteins, bovine milk proteins are probably the most well characterized chemically, physically, and genetically. The primary structures are known for most genetic variants of alpha s1-, alpha s2-, beta-, and kappa-caseins, beta-lactoglobulin, and alpha-lactalbumin. Secondary and tertiary structures of the whey proteins have been determined, and secondary structures of the caseins have been predicted from spectral studies. The caseins, although less ordered in structure and more flexible than the typical globular whey proteins, have significant amounts of secondary and, probably, tertiary structure. The amphipathic structure of the caseins is especially noteworthy; thus, these proteins most likely are divided into polar and hydrophobic domains. The presence of anionic phosphoseryl residue clusters in the calcium-sensitive casein polar domains is particularly significant because of their interaction with calcium ions, or calcium salts, or both, and the formation of micelles. Flexibility of casein structures is reflected by their susceptibilities to limited proteolysis, which dramatically changes functionality.}, number={10}, journal={JOURNAL OF DAIRY SCIENCE}, author={SWAISGOOD, HE}, year={1993}, month={Oct}, pages={3054–3061} }
 @article{swaisgood_1992, title={Review and update of milk protein chemistry}, volume={75}, journal={Journal of Dairy Science}, author={Swaisgood, H. E.}, year={1992}, pages={89} }
 @article{swaisgood_catignani_1991, title={Protein digestibility: In vitro methods of assessment}, volume={35}, DOI={10.1016/s1043-4526(08)60065-0}, abstractNote={This chapter describes those changes in protein structure that lead to change in the digestibility of the protein and discusses several methods for assaying protein digestibility The biological utilization of a protein is primarily dependent on its digestibility by gastric, pancreatic, and intestinal peptidases; its composition, particularly with respect to the essential amino acids; and the absorption or transport of amino acids and di- and tri-peptides into the blood. In vitro methods plays an important role in assaying protein digestibility, because these methods are more rapid, simple, and potentially could be used commercially for monitoring protein quality. Modifications that commonly affect protein digestibility include proteolysis, thermal unfolding, aggregation, carbonyl-amine reactions, racemization, and cross-linking. The digestion of protein in vivo depends on the accessibility and flexibility of the polypeptide chain. The structure of many proteins is destabilized by the acid conditions of the stomach that aids their hydrolysis and further destabilization by pepsin.}, journal={Advances in Food and Nutrition Research}, author={Swaisgood, H. E. and Catignani, G. L.}, year={1991}, pages={185} }
 @article{swaisgood_harwalkar_1990, title={BORDEN SYMPOSIUM ON STABILITY OF MILK-PROTEINS IN DAIRY FOODS}, volume={73}, ISSN={["0022-0302"]}, DOI={10.3168/jds.S0022-0302(90)79061-3}, abstractNote={The three-dimensional structure of proteins exhibits marginal stability even under physiological conditions. Any deviation of the environment from the physiological state may result in perturbation of the protein's structure. Under appropriate conditions, the structural transition may be reversible (Figure 1). For example, for several proteins, the native structure can be reformed by refolding proteins from a random coil state. However, for many proteins, refolding in solution leads to kinetically trapped nonnative states due to intermolecular interaction. Swaisgood proposed the principle of physical isolation of nascent folding polypeptide chains and has shown that even proteins that cannot be refolded in solution to give biologically active structure can be refolded to the native state if the folding molecules are physically isolated by immobilization. In principle, any protein, even those kinetically trapped in nonnative states, can be refolded to the native state by passing through the random coil state (Figure 1). In food systems, these conditions for reformation of native structure are infrequently observed. Hence, any substantial structural perturbation due to salt, pH, alcohol, or heat treatment leads to irreversible changes in protein structure, even if a simulated physiological environment is restored. The nonnative structures thus formed have properties that are different from those of the native protein. Conse-}, number={12}, journal={JOURNAL OF DAIRY SCIENCE}, author={SWAISGOOD, HE and HARWALKAR, VR}, year={1990}, month={Dec}, pages={3591–3591} }
 @article{swaisgood_horton_1989, title={Immobilized enzymes as processing aids or analytical tools}, DOI={10.1021/bk-1989-0389.ch017}, abstractNote={The primary products of agriculture are biological materials; therefore, the use of enzymes as processing aids and analytical tools would seem to be a natural consequence. Nevertheless, the number of enzymes actually used commercially is quite small in comparison with the total number of enzymes which have been characterized. Essentially, only hydrolases have been extensively developed as processing catalysts and analytical reagents, although there are certain important exceptions including isomerases, lyases and oxidases. Enzymes can be used in either soluble or immobilized forms. In some cases, use of soluble enzymes requires incorporation of a subsequent inactivation step. Immobilized enzymes provide opportunities for process control and automation, and may stabilize the catalyst to conditions required in a given process. However, the operation of an immobilized enzyme bioreactor must be compatible with the entire process, and a bioreactor's half-life must be sufficiently long to compensate for its added cost. The recent advent of recombinant DNA technology and site-directed mutagenesis should increase the potential for using enzymes of greater stability and modified specificities.}, number={389}, journal={ACS Symposium Series}, author={Swaisgood, H. E. and Horton, H. R.}, year={1989}, pages={242} }
 @inbook{swaisgood_1989, title={Structural changes in milk proteins}, ISBN={3798507864}, DOI={10.1007/978-3-642-85373-9_30}, abstractNote={With the growing body of knowledge of protein structure has come the realization that proteins are not rigid, inflexible structures. Rather their structures are dynamic and are characterized by marginal stability and conformational equilibria. Their structures represent a minimization of the sum of the free energies resulting from noncovalent interactions between amino acid residues within a polypeptide chain, between residues in contacting polypeptide chains, and between residues and solvent molecules. Because of their marginal stability, protein structures are sensitive to environmental change and alteration in their structure may be reversible or irreversible. Neglecting postsynthetic covalent change, proteins will refold to their native conformation from a random coil state under conditions which mimic the physiological environment. This result is a consequence of the thermodynamic nature of their structural stabilization. Recent evidence suggests that folding pathways as well as the native structures are determined by the primary structure and the consequent thermodynamics of noncovalent interactions between residues and residues plus solvent [1].}, booktitle={Milk proteins: nutritional, clinical, functional and technological aspects}, publisher={Darmstadt: Steinkopff}, author={Swaisgood, H. E.}, editor={C. A. Barth and Schlimme, E.Editors}, year={1989}, pages={192} }
 @article{church_swaisgood_porter_catignani_1983, title={SPECTROPHOTOMETRIC ASSAY USING ORTHO-PHTHALDIALDEHYDE FOR DETERMINATION OF PROTEOLYSIS IN MILK AND ISOLATED MILK-PROTEINS}, volume={66}, ISSN={["0022-0302"]}, DOI={10.3168/jds.S0022-0302(83)81926-2}, abstractNote={Abstract A rapid, sensitive, and convenient Spectrophotometric assay was developed and characterized for measurement of proteolysis of milk proteins in buffered solutions or in milk. α -Amino groups released by hydrolysis react with ο -phthaldialdehyde and ( β -mercaptoethanol to form an adduct that absorbs strongly at 340nm. The absorptivity ( ɛ = 6000M −1 cm −1 ) is similar for all α -amino groups. Moreover, the absorptivity of the adduct with both α - and ɛ -amino groups of proteins is also similar and unaffected by local environment when proteins are denatured in sodium dodecyl sulfate. Thus, background is constant for a particular sample, and α -amino groups released by proteolysis can be quantitated accurately. Inclusion of sodium dodecyl sulfate in the assay provides a convenient way to terminate proteolysis and to insure full exposure and complete reaction of amino groups. Because all hydrolytic products are assayed, the method is more accurate than procedures that depend upon properties of aromatic residues (Hull and Lowry methods). Furthermore, the o-phthaldialdehyde Spectrophotometric assay is more rapid and convenient than methods using ninhydrin, 2,4,6-trinitrobenzenesulfonic acid, or fluorescamine. The assay proved to be especially useful for measuring proteolysis in milk from microbial culture organisms such as Streptococcus lactis C2. Because trichloroacetic acid filtrates are used, the method should be adaptable to other dairy products.}, number={6}, journal={JOURNAL OF DAIRY SCIENCE}, author={CHURCH, FC and SWAISGOOD, HE and PORTER, DH and CATIGNANI, GL}, year={1983}, pages={1219–1227} }