@article{walker_harden_suyemoto_thakur_jacob_borst_2023, title={Draft Genome Sequences of Escherichia coli and Enterococcus faecalis Coisolated from Polymicrobial Extraintestinal Infections of Chickens and Turkeys}, volume={2}, ISSN={["2576-098X"]}, DOI={10.1128/mra.01163-22}, abstractNote={Coinfections by avian pathogenic Escherichia coli (APEC) and Enterococcus faecalis in poultry with colisepticemia have become increasingly recognized. Here, we report draft genome sequences of 18 APEC and 18 E. faecalis strains coisolated from lesions of diseased poultry. ABSTRACT Coinfections by avian pathogenic Escherichia coli (APEC) and Enterococcus faecalis in poultry with colisepticemia have become increasingly recognized. Here, we report draft genome sequences of 18 APEC and 18 E. faecalis strains coisolated from lesions of diseased poultry.}, journal={MICROBIOLOGY RESOURCE ANNOUNCEMENTS}, author={Walker, Grayson K. and Harden, Lyndy and Suyemoto, M. Mitsu and Thakur, Siddhartha and Jacob, Megan and Borst, Luke B.}, year={2023}, month={Feb} }
 @article{walker_harden_suyemoto_thakur_jacob_borst_2023, title={Draft genome sequences of 12 Escherichia coli co-isolated with Enterococcus spp. from dogs with polybacterial bacteriuria at a veterinary hospital}, volume={8}, ISSN={["2576-098X"]}, DOI={10.1128/MRA.00262-23}, abstractNote={ABSTRACT Escherichia coli are frequently co-isolated with Enterococcus spp. from urine cultures of dogs with urinary tract infections (UTIs). Uropathogenic E. coli (UPEC) are augmented by Enterococcus in polymicrobial UTIs. We report the draft genome sequences of 12 UPEC co-isolated with Enterococcus spp. from canine urinary tract infections.}, journal={MICROBIOLOGY RESOURCE ANNOUNCEMENTS}, author={Walker, Grayson K. and Harden, Lyndy and Suyemoto, M. Mitsu and Thakur, Siddhartha and Jacob, Megan and Borst, Luke B.}, year={2023}, month={Aug} }
 @article{cruz_haeberle_westerman_durham_suyemoto_knodler_elfenbein_2023, title={Nonredundant Dimethyl Sulfoxide Reductases Influence Salmonella enterica Serotype Typhimurium Anaerobic Growth and Virulence}, ISSN={["1098-5522"]}, DOI={10.1128/iai.00578-22}, abstractNote={Facultative anaerobic enteric pathogens can utilize a diverse array of alternate electron acceptors to support anaerobic metabolism and thrive in the hypoxic conditions within the mammalian gut. Dimethyl sulfoxide (DMSO) is produced by methionine catabolism and can act as an alternate electron acceptor to support anaerobic respiration. ABSTRACT Facultative anaerobic enteric pathogens can utilize a diverse array of alternate electron acceptors to support anaerobic metabolism and thrive in the hypoxic conditions within the mammalian gut. Dimethyl sulfoxide (DMSO) is produced by methionine catabolism and can act as an alternate electron acceptor to support anaerobic respiration. The DMSO reductase complex consists of three subunits, DmsA, DmsB, and DmsC, and allows bacteria to grow anaerobically with DMSO as an electron acceptor. The genomes of nontyphoidal Salmonella enterica encode three putative dmsABC operons, but the impact of the apparent genetic redundancy in DMSO reduction on the fitness of nontyphoidal S. enterica during infection remains unknown. We hypothesized that DMSO reduction would be needed for S. enterica serotype Typhimurium to colonize the mammalian gut. We demonstrate that an S. Typhimurium mutant with loss of function in all three putative DMSO reductases (ΔdmsA3) poorly colonizes the mammalian intestine when the microbiota is intact and when inflammation is absent. DMSO reduction enhances anaerobic growth through nonredundant contributions of two of the DMSO reductases. Furthermore, DMSO reduction influences virulence by increasing expression of the type 3 secretion system 2 and reducing expression of the type 3 secretion system 1. Collectively, our data demonstrate that the DMSO reductases of S. Typhimurium are functionally nonredundant and suggest DMSO is a physiologically relevant electron acceptor that supports S. enterica fitness in the gut.}, journal={INFECTION AND IMMUNITY}, author={Cruz, E. and Haeberle, A. L. and Westerman, T. L. and Durham, M. E. and Suyemoto, M. M. and Knodler, L. A. and Elfenbein, J. R.}, year={2023}, month={Feb} }
 @article{walker_suyemoto_hull_gall_jimenez_chen_thakur_crespo_borst_2021, title={Genomic Characterization of a Nalidixic Acid-Resistant Salmonella Enteritidis Strain Causing Persistent Infections in Broiler Chickens}, volume={8}, ISSN={["2297-1769"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85115006803&partnerID=MN8TOARS}, DOI={10.3389/fvets.2021.725737}, abstractNote={Virulent strains of Salmonella enterica subsp. enterica serovar Enteritidis (SE) harbored by poultry can cause disease in poultry flocks and potentially result in human foodborne illness. Two broiler flocks grown a year apart on the same premises experienced mortality throughout the growing period due to septicemic disease caused by SE. Gross lesions predominantly consisted of polyserositis followed by yolk sacculitis, arthritis, osteomyelitis, and spondylitis. Tissues with lesions were cultured yielding 59 SE isolates. These were genotyped by Rep-PCR followed by whole-genome sequencing (WGS) of 15 isolates which were clonal. The strain, SE_TAU19, was further characterized for antimicrobial susceptibility and virulence in a broiler embryo lethality assay. SE_TAU19 was resistant to nalidixic acid and sulfadimethoxine and was virulent to embryos with 100% mortality of all challenged broiler embryos within 3.5 days. Screening the SE_TAU19 whole-genome sequence revealed seven antimicrobial resistance (AMR) genes, 120 virulence genes, and two IncF plasmid replicons corresponding to a single, serovar-specific pSEV virulence plasmid. The pef, spv, and rck virulence genes localized to the plasmid sequence assembly. We report phenotypic and genomic features of a virulent SE strain from persistently infected broiler flocks and present a workflow for SE characterization from isolate collection to genome assembly and sequence analysis. Further SE surveillance and investigation of SE virulence in broiler chickens is warranted.}, journal={FRONTIERS IN VETERINARY SCIENCE}, author={Walker, Grayson K. K. and Suyemoto, M. Mitsu and Hull, Dawn M. M. and Gall, Sesny and Jimenez, Fernando and Chen, Laura R. R. and Thakur, Siddhartha and Crespo, Rocio and Borst, Luke B. B.}, year={2021}, month={Sep} }
 @article{walker_suyemoto_borst_brake_2020, title={Research Note: Repetitive element-based polymerase chain reaction genotyping improves efficiency of Salmonella surveillance in a model broiler production system}, volume={99}, ISSN={["1525-3171"]}, DOI={10.1016/j.psj.2019.12.048}, abstractNote={The genetic relatedness and antimicrobial susceptibility profiles of Salmonella isolated from poultry and their environment were determined. One broiler breeder flock (BBF1) and 2 broiler flocks (BF1 and BF2) were reared over a 1.75-year period on the same poultry research farm. Hatching eggs were obtained from BBF1 to produce BF1 chicks, while BF2 chicks were progeny of a separate, unsampled broiler breeder flock. BF1 and BF2 were reared in the same housing facilities but 6 mo apart. Salmonella isolates were collected via litter sock sampling (BF1), cecal excision (BF1 and BF2), or cloacal swabs (BBF1). Serotyping identified Salmonella enterica subsp. enterica serovar Altona (SA) in BBF1 and S. enterica subsp. enterica serovar Senftenberg (SS) in BF1 and BF2. Genotypic fingerprinting was achieved with Rep-PCR using the (GTG)5 primer and revealed sequence homology among Senftenberg isolates from BF1 and BF2. For each isolate, the minimum inhibitory concentration was determined for 27 antimicrobial agents using Sensititre plates with formularies specific to antimicrobials used in poultry production or those used to control gram negative pathogens. Isolates from the 3 flocks were resistant to clindamycin, erythromycin, novobiocin, penicillin, and tylosin tartrate and demonstrated intermediate resistance to azithromycin, florfenicol, and spectinomycin. These data demonstrated that serovar Altona and Senftenberg were harbored by poultry, the latter appeared to persist in broiler flocks, and both serotypes shared similar patterns of antimicrobial susceptibility in an integrated research operation. In the case of multiple Salmonella isolates, combining genotypic fingerprinting methods with serotyping of representative isolates would reduce the number of samples required for serotyping and more clearly identify relatedness of isolates. These methods facilitate effective surveillance in poultry production systems, thus allowing for implementation of precise Salmonella control measures.}, number={5}, journal={POULTRY SCIENCE}, author={Walker, G. K. and Suyemoto, M. M. and Borst, L. B. and Brake, J.}, year={2020}, month={May}, pages={2684–2689} }
 @article{walker_suyemoto_gall_chen_thakur_borst_2020, title={The role ofEnterococcus faecalisduring co-infection with avian pathogenicEscherichia coliin avian colibacillosis}, volume={49}, ISSN={["1465-3338"]}, url={http://dx.doi.org/10.1080/03079457.2020.1796926}, DOI={10.1080/03079457.2020.1796926}, abstractNote={ABSTRACT Enterococcus spp. (ENT) are frequently co-isolated with avian pathogenic E. coli (APEC) from poultry with colibacillosis, a leading cause of flock mortality. Although largely overlooked, ENT may play an active role in these infections. To assess the frequency of ENT co-isolation in colibacillosis, cultures were collected from birds with gross lesions of omphalitis, polyserositis, and septicaemia over a 3-year period from three turkey flocks and three broiler flocks. In birds diagnosed with colibacillosis based on gross findings and isolation of E. coli, ENT were co-isolated with APEC in 35.7% (n = 41/115) of colibacillosis mortality and 3.7% of total mortality (n = 41/1122). Co-isolated APEC and ENT pairs (n = 41) were further characterized using antimicrobial resistance phenotyping and in vitro co-culture assays. E. faecalis (EF) was the most commonly co-isolated species (68% n = 28/41) and tetracycline resistance was the resistance phenotype most commonly found among APEC (51% n = 21/41) and ENT (93% n = 38/41). Under iron-restricted conditions, EF enhanced APEC growth in a proximity-dependent manner and APEC grown in mixed culture with EF exhibited a significant growth and survival advantage (P ≤ 0.01). In an embryo lethality assay, APEC co-infection with EF resulted in decreased survival of broiler embryos compared to mono-infections (P ≤ 0.05). These data demonstrate that EF augmented APEC survival and growth under iron limiting conditions, possibly translating to the increased virulence of APEC in broiler embryos. Thus, ENT co-infections may be a previously unrecognized contributor to colibacillosis-related mortality. Further investigations into the mechanism of this interaction are warranted. RESEARCH HIGHLIGHTS Enterococcus is frequently co-isolated with avian pathogenic E. coli (APEC). Enterococcus faecalis (EF) enhances survival of APEC in iron restricted conditions. EF co-infection increases APEC virulence in broiler embryos.}, number={6}, journal={AVIAN PATHOLOGY}, publisher={Informa UK Limited}, author={Walker, Grayson K. and Suyemoto, M. Mitsu and Gall, Sesny and Chen, Laura and Thakur, Siddhartha and Borst, Luke B.}, year={2020}, month={Nov}, pages={589–599} }
 @article{chen_suyemoto_sarsour_cordova_oviedo-rondon_wineland_barnes_borst_2019, title={Temporal characterization of wooden breast myopathy ("woody breast") severity and correlation with growth rate and lymphocytic phlebitis in three commercial broiler strains and a random-bred broiler strain}, volume={48}, ISSN={["1465-3338"]}, DOI={10.1080/03079457.2019.1598541}, abstractNote={ABSTRACT Wooden breast myopathy (WBM), or “woody breast” or “wooden breast” affects modern, rapidly growing, high breast-yield broiler chickens. Decreased meat quality due to undesirable organoleptic properties and condemnation of affected breast meat cause economic losses. The pathogenesis of WBM remains unknown. In this study, WBM lesion development was determined in three modern broiler strains and Athens Canadian Random Bred (ACRB) broilers, a 1950s unselected broiler chicken. Correlations between WBM severity and incubation temperature profile, sex, strain, body weight, and lymphocytic phlebitis were also determined. At 2, 4, 6, and 8 weeks of age, samples of breast muscle from 10 male and 10 female birds from each strain, incubated under optimal or low-early, high-late temperatures, were scored histologically for severity of WBM and lymphocytic phlebitis. WBM lesions, identified as early as 2 weeks, became progressively more severe with age and growth in the three commercial broiler strains. WBM severity was significantly correlated with lymphocytic phlebitis and body weight. Lymphocytic phlebitis and minimal WBM were present in the ACRB broilers at all samplings, but did not progress in severity over time. There were no significant differences in severity of WBM among the commercial broiler strains, between sexes, or between incubation temperature profiles. The positive correlation between WBM severity and lymphocytic phlebitis indicates vascular injury is likely an important factor in the pathogenesis. Mild muscle lesions in ACRB birds without overt clinical signs indicate subclinical muscle disease may have been present in broilers prior to the description of WBM.}, number={4}, journal={AVIAN PATHOLOGY}, author={Chen, Laura R. and Suyemoto, M. Mitsu and Sarsour, Albarra H. and Cordova, H. Alejandro and Oviedo-Rondon, Edgar O. and Wineland, Michael and Barnes, H. John and Borst, Luke B.}, year={2019}, month={Jul}, pages={319–328} }
 @article{borst_suyemoto_chen_barnes_2019, title={Vaccination of breeder hens with a polyvalent killed vaccine for pathogenic Enterococcus cecorum does not protect offspring from enterococcal spondylitis}, volume={48}, ISSN={["1465-3338"]}, url={https://doi.org/10.1080/03079457.2018.1536819}, DOI={10.1080/03079457.2018.1536819}, abstractNote={ABSTRACT Pathogenic strains of Enterococcus cecorum cause symmetrical paralysis in broilers due to infection of the free thoracic vertebra. The disease caused by pathogenic E. cecorum, known as enterococcal spondylitis or “kinky-back” continues to be responsible for significant losses to the broiler industry worldwide. In outbreaks of pathogenic E. cecorum, gut colonization and sepsis occur in the first three weeks-of-life. Since maternal antibodies are present during this period, we postulated that vaccination of breeders with a polyvalent killed vaccine would protect chicks from challenge. To test this hypothesis, representative isolates from seven genotype groups of pathogenic E. cecorum circulating in the US were chosen to produce adjuvanted killed vaccines (bacterins) and given to broiler-breeder hens. No single strain produced high titres of antibodies to all other strains; however, the combination of serologic reactivity of pathogenic isolates (designated SA3 and SA7) was sufficient to react with all genotypes. Vaccination of commercial broiler-breeder hens with a bacterin composed of SA3 and SA7 did not have any adverse effects. Vaccinated hens developed E. cecorum specific antibodies; however, no significant difference in survival was observed in infected embryos from hens in vaccine or adjuvant only groups. Chicks from vaccinated hens also failed to resist homologous or heterologous challenge during experimental infection. In a macrophage killing assay, pathogenic E. cecorum were found to evade opsinophagocytosis with elicited antibodies. These data suggest that pathogenic strains of E. cecorum possess virulence mechanisms that confound antibody-mediated opsinophagocytosis, complicating vaccine development for this pathogen of broilers.}, number={1}, journal={AVIAN PATHOLOGY}, author={Borst, Luke B. and Suyemoto, M. Mitsu and Chen, Laura R. and Barnes, H. John}, year={2019}, month={Jan}, pages={17–24} }
 @article{gall_suyemoto_sather_sharpton_barnes_borst_2019, title={Wooden Breast in Commercial Broilers Associated with Mortality, Dorsal Recumbency, and Pulmonary Disease}, volume={63}, ISSN={["1938-4351"]}, DOI={10.1637/11995-111218-Case.1}, abstractNote={SUMMARY. Occurrence of mortality, wooden breast, and pulmonary disease in broiler chickens during the last 16 days of production in a teaching flock of 4000 commercial broilers was determined. A new syndrome was identified, in which broilers fell over for an unknown reason and were unable to right themselves (dorsal recumbency). Birds affected by dorsal recumbency were alert and responsive and showed no clinical signs except for occasional mild to moderate dyspnea. When turned over, they resumed normal behavior. Mortality (14 culls; 49 dead) during the last 16 days of production accounted for 1.6% of the flock and 36% of total mortality. Among these, 71% were heavy males, 70% had wooden breast, and 71% had pulmonary congestion and edema. Gross lesions of concurrent wooden breast and pulmonary disease occurred in 68% of the mortality, including 21 of 22 dead birds found on their backs. These findings indicate that wooden breast is associated with mortality prior to processing as a result of pulmonary disease in heavy male broilers. When birds with wooden breast fall onto their backs for unknown reason(s), they are unable to right themselves. If not found and turned over, they may not survive. Based on these findings, wooden breast is likely greater than just a problem with meat quality and should be considered an animal well-being issue.}, number={3}, journal={AVIAN DISEASES}, author={Gall, Sesny and Suyemoto, M. Mitsu and Sather, Hannah M. L. and Sharpton, A. Richard and Barnes, H. John and Borst, Luke B.}, year={2019}, month={Sep}, pages={514–519} }
 @article{suyemoto_barnes_borst_2017, title={Culture methods impact recovery of antibiotic-resistant Enterococci including Enterococcus cecorum from pre- and postharvest chicken}, volume={64}, ISSN={["1472-765X"]}, DOI={10.1111/lam.12705}, abstractNote={Pathogenic strains of Enterococcus cecorum (EC) expressing multidrug resistance have emerged. In National Antimicrobial Resistance Monitoring System (NARMS) data, EC is rarely recovered from chickens. Two NARMS methodologies (FDA and USDA) were compared with standard culture (SC) techniques for recovery of EC. NARMS methods failed to detect EC in 58 caecal samples, 20 chicken breast or six whole broiler samples. EC was recovered from 1 of 38 (2·6%) and 2 of 38 (5·2%) preharvest spinal lesions (USDA and FDA method, respectively). In contrast, using the SC method, EC was recovered from 44 of 53 (83%) caecal samples, all 38 (100%) spinal lesions, 14 of 20 (70%) chicken breast samples, and all three spinal lesions identified in whole carcasses. Compared with other Enterococcus spp., EC isolates had a higher prevalence of resistance to macrolides. The NARMS methods significantly affected recovery of enterococcal species other than EC. When the postharvest FDA method was applied to preharvest caecal samples, isolates of Enterococcus faecium were preferentially recovered. All 11 E. faecium isolates were multidrug resistant, including resistance to penicillin, daptomycin and linezolid. These findings confirm that current methodologies may not accurately identify the amount and range of antimicrobial resistance of enterococci from chicken sources.}, number={3}, journal={LETTERS IN APPLIED MICROBIOLOGY}, author={Suyemoto, M. M. and Barnes, H. J. and Borst, L. B.}, year={2017}, month={Mar}, pages={210–216} }
 @article{chen_suyemoto_sarsour_cordova_oviedo-rondón_barnes_borst_2017, title={Prevalence and severity of osteochondrosis of the free thoracic vertebra in three modern broiler strains and the Athens Canadian Random Bred control broiler}, volume={47}, ISSN={0307-9457 1465-3338}, url={http://dx.doi.org/10.1080/03079457.2017.1388499}, DOI={10.1080/03079457.2017.1388499}, abstractNote={ABSTRACT Osteochondrosis (OCD) results from a disturbance of endochondral ossification in articular cartilage and is an important cause of lameness in several animal species, including chickens. OCD lesions in the free thoracic vertebra (FTV) of chickens are essential to the pathogenesis of pathogenic Enterococcus cecorum. The goal of this study was to determine the prevalence of OCD in the FTV among three modern broiler chicken crosses (strains A/A, A/B, and C/C) and Athens Canadian Random Bred (ACRB) chickens, which served as the control group. The effect of sex, age, strain, body weight, and incubation temperature profile on OCD severity for each group was determined. At 2, 4, 6, and 8 weeks of age, the FTV of 10 male and 10 female birds from each strain exposed to either optimal or low-early, high-late incubation temperature profiles were collected and scored histologically for OCD lesion severity. OCD spectrum lesions were detected in >70% of all strain/sex combinations, including the ACRB controls. No association was observed between mean OCD score and broiler strain, incubation temperature profile, sex, age, or body weight. These findings indicate that OCD of the FTV is common in broiler chickens with similar prevalence observed in broilers with modern genetics and the ACRB broilers which represent 1950s broiler genetics. As the parameters examined did not have a statistical correlation with OCD, additional work is needed to understand factors that contribute to development of OCD in chickens.}, number={2}, journal={Avian Pathology}, publisher={Informa UK Limited}, author={Chen, Laura R. and Suyemoto, M. Mitsu and Sarsour, Albarra H. and Cordova, H. Alejandro and Oviedo-Rondón, Edgar O. and Barnes, H. John and Borst, Luke B.}, year={2017}, month={Nov}, pages={152–160} }
 @article{borst_suyemoto_sarsour_harris_martin_strickland_oviedo_barnes_2016, title={Pathogenesis of Enterococcal Spondylitis Caused by Enterococcus cecorum in Broiler Chickens}, volume={54}, ISSN={0300-9858 1544-2217}, url={http://dx.doi.org/10.1177/0300985816658098}, DOI={10.1177/0300985816658098}, abstractNote={ Enterococcal spondylitis (ES) is a disease of commercial broiler chickens, with a worldwide distribution. Symmetrical hind limb paralysis typical of ES results from infection of the free thoracic vertebra (FTV) by pathogenic strains of Enterococcus cecorum . To determine the pathogenesis of ES, birds with natural and experimental ES were studied over time. In natural disease, case birds (n = 150) from an affected farm and control birds (n = 100) from an unaffected farm were evaluated at weeks 1–6. In control birds, intestinal colonization by E. cecorum began at week 3. In case birds, E. cecorum was detected in intestine and spleen at week 1, followed by infection of the FTV beginning at week 3. E. cecorum isolates recovered from intestine, spleen, and FTV of case birds had matching genotypes, confirming that intestinal colonization with pathogenic strains precedes bacteremia and infection of the FTV. Clinical intestinal disease was not required for E. cecorum bacteremia. In 1- to 3-week-old case birds, pathogenic E. cecorum was observed within osteochondrosis dissecans (OCD) lesions in the FTV. To determine whether OCD of the FTV was a risk factor for ES, 214 birds were orally infected with E. cecorum, and the FTV was evaluated histologically at weeks 1–7. Birds without cartilage clefts of OCD in the FTV did not develop ES; while birds with OCD scores ≥3 were susceptible to lesion development. These findings suggest that intestinal colonization, bacteremia, and OCD of the FTV in early life are crucial to the pathogenesis of ES. }, number={1}, journal={Veterinary Pathology}, publisher={SAGE Publications}, author={Borst, L. B. and Suyemoto, M. M. and Sarsour, A. H. and Harris, M. C. and Martin, M. P. and Strickland, J. D. and Oviedo, E. O. and Barnes, H. J.}, year={2016}, month={Aug}, pages={61–73} }
 @article{borst_suyemoto_scholl_fuller_barnes_2015, title={Comparative Genomic Analysis Identifies Divergent Genomic Features of Pathogenic Enterococcus cecorum Including a Type IC CRISPR-Cas System, a Capsule Locus, an epa-Like Locus, and Putative Host Tissue Binding Proteins}, volume={10}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0121294}, abstractNote={Enterococcus cecorum (EC) is the dominant enteric commensal of adult chickens and contributes to the gut consortia of many avian and mammalian species. While EC infection is an uncommon zoonosis, like other enterococcal species it can cause life-threating nosocomial infection in people. In contrast to other enterococci which are considered opportunistic pathogens, emerging pathogenic strains of EC cause outbreaks of musculoskeletal disease in broiler chickens. Typical morbidity and mortality is comparable to other important infectious diseases of poultry. In molecular epidemiologic studies, pathogenic EC strains were found to be genetically clonal. These findings suggested acquisition of specific virulence determinants by pathogenic EC. To identify divergent genomic features and acquired virulence determinants in pathogenic EC; comparative genomic analysis was performed on genomes of 3 pathogenic and 3 commensal strains of EC. Pathogenic isolates had smaller genomes with a higher GC content, and they demonstrated large regions of synteny compared to commensal isolates. A molecular phylogenetic analysis demonstrated sequence divergence in pathogenic EC genomes. At a threshold of 98% identity, 414 predicted proteins were identified that were highly conserved in pathogenic EC but not in commensal EC. Among these, divergent CRISPR-cas defense loci were observed. In commensal EC, the type IIA arrangement typical for enterococci was present; however, pathogenic EC had a type IC locus, which is novel in enterococci but commonly observed in streptococci. Potential mediators of virulence identified in this analysis included a polysaccharide capsular locus similar to that recently described for E. faecium, an epa-like locus, and cell wall associated proteins which may bind host extracellular matrix. This analysis identified specific genomic regions, coding sequences, and predicted proteins which may be related to the divergent evolution and increased virulence of emerging pathogenic strains of EC.}, number={4}, journal={PLOS ONE}, author={Borst, Luke B. and Suyemoto, M. Mitsu and Scholl, Elizabeth H. and Fuller, Fredrick J. and Barnes, H. John}, year={2015}, month={Apr} }
 @article{borst_suyemoto_keelara_dunningan_guy_barnes_2014, title={A Chicken Embryo Lethality Assay for Pathogenic Enterococcus cecorum}, volume={58}, ISSN={["1938-4351"]}, DOI={10.1637/10687-101113-reg.1}, abstractNote={SUMMARY Pathogenic strains of Enterococcus cecorum cause outbreaks of arthritis and osteomyelitis in chickens worldwide. Enterococcal spondylitis (ES) is a specific manifestation of E. cecorum-associated disease of broilers and broiler breeders characterized by increased flock mortality, resulting from unresolved infection of the free thoracic vertebra by pathogenic E. cecorum. A study of 22 ES outbreaks in the southeast United States revealed that pathogenic E. cecorum strains isolated from spinal lesions were genetically clonal. Here, we compare the virulence of previously genotyped pathogenic strains (n  =  8) isolated from spinal lesions and nonpathogenic strains (n  =  9) isolated from ceca of unaffected birds in a chicken embryo lethality model. Strains were inoculated into the allantoic cavity of 12-day-old broiler and specific-pathogen-free (SPF) layer embryos; embryo survival was determined by candling eggs daily for 4 days. Significantly decreased survival occurred in both broiler and SPF embryos inoculated with pathogenic genotype strains compared with embryos inoculated with nonpathogenic genotype strains (broiler embryos, 23% vs. 60%; SPF embryos, 9% vs. 61%). Embryos infected with pathogenic strains were unable to control infection and consistently showed gross changes typical of sepsis, including hemorrhage and edema. After 48 hr, similar changes were not observed in embryos infected with nonpathogenic strains. This embryo lethality assay provides a useful tool for understanding the genetic basis of E. cecorum virulence. RESUMEN Ensayo de letalidad en embriones de pollo para cepas de Enterococcus cecorum patogénicas. Las cepas patógenas de Enterococcus cecorum causan brotes de artritis y osteomielitis en pollos a nivel mundial. La espondilitis enterococócica (ES) es una manifestación específica de la enfermedad asociada con E. cecorum en pollos de engorde y en reproductoras pesadas que es caracterizada por alta mortalidad de la parvada, como resultado de la infección no resuelta en la vértebra torácica móvil causada por cepas de E. cecorum patógenas. Un estudio de 22 brotes de espondilitis enterococócica en el sureste de los Estados Unidos reveló que las cepas patógenas de E. cecorum aisladas de lesiones de la médula eran genéticamente provenientes de un clon. En este estudio, se comparó mediante un modelo de letalidad del embrión de pollo, la virulencia de las cepas patógenas previamente genotipificadas (n = 8) aisladas de lesiones de la columna vertebral y cepas no patógenas (n = 9) aisladas del ciego de las aves no afectadas. Las cepas fueron inoculadas en la cavidad alantoidea de embriones de pollo de 12 días de edad, de pollos de engorde y en aves libres de patógenos específicos (SPF); la supervivencia de los embriones se determinó por ovoscopía diariamente por cuatro días. De manera significativa se presentó una disminución en la supervivencia en ambos tipo embriones de pollos de engorde y de aves libres de patógenos específicos inoculados con cepas de genotipo patógeno en comparación con los embriones inoculados con cepas de genotipo no patógeno (embriones de pollos de engorde, 23% contra 60%; y en los embriones libres de patógenos específicos, 9% frente a 61%). Los embriones infectados con cepas patógenas fueron incapaces de controlar la infección y mostraron consistentemente cambios macroscópicos típicos de sepsis, incluyendo hemorragia y edema. Después de 48 horas, no se observaron cambios similares en los embriones infectados con cepas no patógenas. Este ensayo de letalidad del embrión proporciona una herramienta útil para la comprensión de la base genética de la virulencia de E. cecorum.}, number={2}, journal={AVIAN DISEASES}, author={Borst, Luke B. and Suyemoto, M. Mitsu and Keelara, Shivaramu and Dunningan, Sarah E. and Guy, James S. and Barnes, H. John}, year={2014}, month={Jun}, pages={244–248} }
 @article{suyemoto_hamrick_spears_horton_washington_havell_borst_orndorff_2013, title={Extrauterine Listeriosis in the gravid mouse influences embryonic growth and development}, volume={8}, number={8}, journal={PLoS One}, author={Suyemoto, M. M. and Hamrick, T. S. and Spears, P. A. and Horton, J. R. and Washington, I. M. and Havell, E. A. and Borst, L. B. and Orndorff, P. E.}, year={2013} }
 @article{ghosh_borst_stauffer_suyemoto_moisan_zurek_gookin_2013, title={Mortality in Kittens Is Associated with a Shift in Ileum Mucosa-Associated Enterococci from Enterococcus hirae to Biofilm-Forming Enterococcus faecalis and Adherent Escherichia coli}, volume={51}, ISSN={["1098-660X"]}, DOI={10.1128/jcm.00481-13}, abstractNote={ABSTRACT}, number={11}, journal={JOURNAL OF CLINICAL MICROBIOLOGY}, author={Ghosh, Anuradha and Borst, Luke and Stauffer, Stephen H. and Suyemoto, Mitsu and Moisan, Peter and Zurek, Ludek and Gookin, Jody L.}, year={2013}, month={Nov}, pages={3567–3578} }
 @article{borst_patterson_lanka_suyemoto_maddox_2013, title={Zebrafish (Danio rerio) as a Screen for Attenuation of Lancefield Group C Streptococci and a Model for Streptococcal Pathogenesis}, volume={50}, ISSN={["1544-2217"]}, DOI={10.1177/0300985811424731}, abstractNote={ Group C streptococci are highly contagious pyogenic bacteria responsible for respiratory tract, lymph node, urogenital tract, and wound infections. Wild-type strains of Streptococcus equi ssp equi ( S. equi) and Streptococcus equi ssp zooepidemicus ( S. zoo) as well as a commercially available modified live vaccine strain of S. equi were evaluated for virulence in zebrafish. Survival times, histologic lesions, and relative gene expression were compared among groups. Based on the intramuscular route of infection, significantly shorter survival times were observed in fish infected with wild-type strain when compared to modified live vaccine and S. zoo strains. Histologically, S. zoo–infected fish demonstrated a marked increase in inflammatory infiltrates (predominantly macrophages) at the site of infection, as well as increased cellularity in the spleen and renal interstitium. In contrast, minimal cellular immune response was observed in S. equi–injected fish with local tissue necrosis and edema predominating. Based on whole comparative genomic hybridization, increased transcription of positive acute-phase proteins, coagulation factors, and antimicrobial peptides were observed in S. equi–injected fish relative to S. zoo–injected fish, while mediators of cellular inflammation, including CXC chemokines and granulin, were upregulated in S. zoo–injected fish relative to S. equi–injected fish. In a screen of 11 clinical isolates, S. equi strains with a single nucleotide deletion in the upstream region of szp, a known virulence factor of streptococci, were found to be significantly attenuated in zebrafish. These collective findings underscore the value of the zebrafish as a model of streptococcal pathogenesis. }, number={3}, journal={VETERINARY PATHOLOGY}, author={Borst, L. B. and Patterson, S. K. and Lanka, S. and Suyemoto, M. M. and Maddox, C. W.}, year={2013}, month={May}, pages={457–467} }
 @article{robbins_suyemoto_lyman_martin_barnes_borst_2012, title={An Outbreak and Source Investigation of Enterococcal Spondylitis in Broilers Caused by Enterococcus cecorum}, volume={56}, ISSN={["0005-2086"]}, DOI={10.1637/10253-052412-case.1}, abstractNote={SUMMARY. Enterococcus cecorum was isolated from spondylitis lesions in broilers from two flocks in North Carolina that were experiencing increased mortality. Affected birds showed paresis and paralysis, clinical signs characteristic of enterococcal spondylitis (ES). Affected birds rested on their hocks and caudal abdomens with legs extended forward and were unable to stand or walk. Necropsy examination of affected birds revealed firm to hard inflammatory masses involving the vertebral bodies at the level of the free thoracic vertebra that bulged dorsally and compressed the spinal cord. When opened, lesions contained pale, tan to yellow caseonecrotic material. Microscopically, necrosis and fibrinoheterophilic spondylitis with intralesional gram-positive bacteria were seen. Heavy growth of E. cecorum recovered from vertebral lesions confirmed the diagnosis of ES. To investigate possible sources of the organism for one of the flocks bacterial cultures were made from the environment, water lines, mice trapped on the farm, cecal/cloacal swabs from one of the parent broiler breeder flocks, egg residue, hatching eggs, and the hatchery environment. Except for cecal/cloacal swabs from the breeders, E. cecorum was not isolated from any of these samples. When compared phenotypically and genotypically, cecal/cloacal isolates of E. cecorum from the breeders differed from isolates from spondylitis lesions in the broilers. The source of E. cecorum for the broiler flocks was not determined, but vertical transmission appears unlikely.}, number={4}, journal={AVIAN DISEASES}, author={Robbins, Kabel M. and Suyemoto, M. Mitsu and Lyman, Roberta L. and Martin, Michael P. and Barnes, H. John and Borst, Luke B.}, year={2012}, month={Dec}, pages={768–773} }
 @article{borst_suyemoto_robbins_lyman_martin_barnes_2012, title={Molecular epidemiology of Enterococcus cecorum isolates recovered from enterococcal spondylitis outbreaks in the southeastern United States}, volume={41}, ISSN={["1465-3338"]}, DOI={10.1080/03079457.2012.718070}, abstractNote={Enterococcus cecorum, a normal intestinal inhabitant, is increasingly responsible for outbreaks of arthritis and osteomyelitis in chickens worldwide. Enterococcal spondylitis (ES) is a specific manifestation of E. cecorum-associated disease in which increased flock morbidity and mortality result from chronic infection involving the free thoracic vertebra. In this study the genetic relatedness and antimicrobial resistance of isolates recovered from ES-affected flocks in the southeastern United States were determined. ES outbreaks from 2007 to 2011 were investigated in North Carolina (15 flocks, 13 farms, four integrators), South Carolina (one flock, one farm, one integrator) and Alabama (six flocks, six farms, one integrator). From these 22 epidemiologically distinct outbreaks, 326 isolates of E. cecorum were recovered. Isolates from spinal lesions and caeca of affected birds (cases) and caeca of unaffected birds (controls) were genotyped using pulsed-field gel electrophoresis; phenotyped using both GenIII MicroPlate™ (Biolog; Hayward, CA, USA) microbial identification plates and antimicrobial sensitivity testing; and compared with each other. Isolates from spinal lesions were incapable of mannitol metabolism and the majority of these isolates were genetically clonal. In contrast, caecal isolates from control birds varied in their ability to metabolize mannitol and were genetically diverse. Isolates from both case and control birds had high levels of antimicrobial resistance. These findings indicate that the increase in E. cecorum-associated disease in the southeast United States is due to the emergence of new clones with increased pathogenicity and multidrug resistance.}, number={5}, journal={AVIAN PATHOLOGY}, author={Borst, Luke B. and Suyemoto, M. Mitsu and Robbins, Kabel M. and Lyman, Roberta L. and Martin, Michael P. and Barnes, H. John}, year={2012}, pages={479–485} }
 @article{spears_suyemoto_hamrick_wolf_havell_orndorff_2011, title={In Vitro Properties of a Listeria monocytogenes Bacteriophage-Resistant Mutant Predict Its Efficacy as a Live Oral Vaccine Strain}, volume={79}, ISSN={["1098-5522"]}, DOI={10.1128/iai.05700-11}, abstractNote={ABSTRACT}, number={12}, journal={INFECTION AND IMMUNITY}, author={Spears, Patricia A. and Suyemoto, M. Mitsu and Hamrick, Terri S. and Wolf, Rebecca L. and Havell, Edward A. and Orndorff, Paul E.}, year={2011}, month={Dec}, pages={5001–5009} }
 @article{suyemoto_spears_hamrick_barnes_havell_orndorff_2010, title={Factors Associated with the Acquisition and Severity of Gestational Listeriosis}, volume={5}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0013000}, abstractNote={Gravid mammals are more prone to listeriosis than their nongravid counterparts. However, many features of the disease in gravid animals are not well defined. We determined, in mice, that increased susceptibility to lethal infection following oral inoculation begins surprisingly early in pregnancy and extends through embryonic development. Pregnancy did not demonstrably increase the spread of listeriae from the intestine to the liver and spleen in the initial 96 h period post inoculation. Consequently, it appeared that gravid animals were competent to contain an enteric infection, but in those instances where escape did occur, a lethal outcome was more likely. Interestingly, colonic colonization level and prevalence, measured 96 h post inoculation, was significantly higher in gravid individuals. In terms of human risk factors for listeriosis, our results suggest that the window of listeriosis susceptibility afforded by pregnancy may be open longer than previously appreciated. Our results also suggest that while gravid animals are competent to contain an enteric infection, enteric carriage rate may be more of a factor in defining disease incidence than previously considered.}, number={9}, journal={PLOS ONE}, author={Suyemoto, M. Mitsu and Spears, Patricia A. and Hamrick, Terri S. and Barnes, Jill A. and Havell, Edward A. and Orndorff, Paul E.}, year={2010}, month={Sep} }
 @article{spears_suyemoto_palermo_horton_hamrick_havell_orndorff_2008, title={A Listeria monocytogenes mutant defective in bacteriophage attachment is attenuated in orally inoculated mice and impaired in enterocyte intracellular growth}, volume={76}, ISSN={["0019-9567"]}, DOI={10.1128/IAI.00283-08}, abstractNote={ABSTRACT}, number={9}, journal={INFECTION AND IMMUNITY}, author={Spears, Patricia A. and Suyemoto, M. Mitsu and Palermo, Angela M. and Horton, John R. and Hamrick, Terri S. and Havell, Edward A. and Orndorff, Paul E.}, year={2008}, month={Sep}, pages={4046–4054} }
 @article{huang_suyemoto_garner_cicconi_altier_2008, title={Formate acts as a diffusible signal to induce Salmonella invasion}, volume={190}, ISSN={["1098-5530"]}, DOI={10.1128/JB.00205-08}, abstractNote={ABSTRACT}, number={12}, journal={JOURNAL OF BACTERIOLOGY}, author={Huang, Yanyan and Suyemoto, Mitsu and Garner, Cherilyn D. and Cicconi, Kellie M. and Altier, Craig}, year={2008}, month={Jun}, pages={4233–4241} }
 @article{lin_yan_huang_altier_li_carrasco_suyemoto_johnston_wang_wang_et al._2007, title={Design and synthesis of boronic-acid-labeled thymidine triphosphate for incorporation into DNA}, volume={35}, DOI={10.1093/nar/gkl1091}, abstractNote={The boronic acid moiety is a versatile functional group useful in carbohydrate recognition, glycoprotein pull-down, inhibition of hydrolytic enzymes and boron neutron capture therapy. The incorporation of the boronic-acid group into DNA could lead to molecules of various biological functions. We have successfully synthesized a boronic acid-labeled thymidine triphosphate (B-TTP) linked through a 14-atom tether and effectively incorporated it into DNA by enzymatic polymerization. The synthesis was achieved using the Huisgen cycloaddition as the key reaction. We have demonstrated that DNA polymerase can effectively recognize the boronic acid-labeled DNA as the template for DNA polymerization, that allows PCR amplification of boronic acid-labeled DNA. DNA polymerase recognitions of the B-TTP as a substrate and the boronic acid-labeled DNA as a template are critical issues for the development of DNA-based lectin mimics via in vitro selection.}, number={4}, journal={Nucleic Acids Research}, author={Lin, N. and Yan, J. and Huang, Z. and Altier, C. and Li, M. Y. and Carrasco, N. and Suyemoto, M. and Johnston, L. and Wang, S. M. and Wang, Q. and et al.}, year={2007}, pages={1222–1229} }
 @article{huang_leming_suyemoto_altier_2007, title={Genome-wide screen of Salmonella genes expressed during infection in pigs, using in vivo expression technology}, volume={73}, ISSN={["1098-5336"]}, DOI={10.1128/AEM.01481-07}, abstractNote={ABSTRACT}, number={23}, journal={APPLIED AND ENVIRONMENTAL MICROBIOLOGY}, author={Huang, Yanyan and Leming, Christopher L. and Suyemoto, Mitsu and Altier, Craig}, year={2007}, month={Dec}, pages={7522–7530} }
 @article{fortune_suyemoto_altier_2006, title={Identification of CsrC and characterization of its role in epithelial cell invasion in Salmonella enterica serovar Typhimurium}, volume={74}, ISSN={["1098-5522"]}, DOI={10.1128/IAI.74.1.331-339.2006}, abstractNote={ABSTRACT}, number={1}, journal={INFECTION AND IMMUNITY}, author={Fortune, DR and Suyemoto, M and Altier, C}, year={2006}, month={Jan}, pages={331–339} }
 @article{lawhon_maurer_suyemoto_altier_2002, title={Intestinal short-chain fatty acids alter Salmonella typhimurium invasion gene expression and virulence through BarA/SirA}, volume={46}, ISSN={["1365-2958"]}, DOI={10.1046/j.1365-2958.2002.03268.x}, abstractNote={Summary}, number={5}, journal={MOLECULAR MICROBIOLOGY}, author={Lawhon, SD and Maurer, R and Suyemoto, M and Altier, C}, year={2002}, month={Dec}, pages={1451–1464} }
 @article{allen_fedorka-cray_vazquez-torres_suyemoto_altier_ryder_fang_libby_2001, title={In Vitro and In Vivo Assessment of Salmonella enterica Serovar Typhimurium DT104 Virulence}, volume={69}, ISSN={0019-9567}, url={http://dx.doi.org/10.1128/iai.69.7.4673-4677.2001}, DOI={10.1128/IAI.69.7.4673-4677.2001}, abstractNote={ABSTRACT}, number={7}, journal={Infection and Immunity}, publisher={American Society for Microbiology}, author={Allen, C. A. and Fedorka-Cray, P. J. and Vazquez-Torres, A. and Suyemoto, M. and Altier, C. and Ryder, L. R. and Fang, F. C. and Libby, S. J.}, year={2001}, month={Jul}, pages={4673–4677} }
 @article{altier_suyemoto_ruiz_burnham_maurer_2000, title={Characterization of two novel regulatory genes affecting Salmonella invasion gene expression}, volume={35}, ISSN={["1365-2958"]}, DOI={10.1046/j.1365-2958.2000.01734.x}, abstractNote={A Salmonella typhimurium chromosomal deletion removing ≈19 kb of DNA at centisome 65 reduces invasion of cultured epithelial cells as well as the expression of lacZY operon fusions to several genes required for the invasive phenotype. As the deleted region contains no genes previously known to affect Salmonella invasion, we investigated the roles of individual genes in the deleted region using a combination of cloning, complementation and directed mutation. We find that the deletion includes two unrelated regulatory genes. One is the Salmonella homologue of Escherichia coli barA (airS ), which encodes a member of the multistep phosphorelay subgroup of two‐component sensor kinases. The action of BarA is coupled to that of SirA, a member of the phosphorylated response regulator family of proteins, and includes both HilA‐dependent and HilA‐independent components. The other regulatory gene removed by the deletion is the Salmonella homologue of E. coli csrB, which specifies a regulatory RNA implicated in controlling specific message turnover in E. coli. These results identify a protein that is likely to play a key role in the environmental control of Salmonella invasion gene expression, and they also suggest that transcriptional control of invasion genes could be subject to refinement at the level of message turnover.}, number={3}, journal={MOLECULAR MICROBIOLOGY}, author={Altier, C and Suyemoto, M and Ruiz, AI and Burnham, KD and Maurer, R}, year={2000}, month={Feb}, pages={635–646} }
 @article{altier_suyemoto_lawhon_2000, title={Regulation of Salmonella enterica serovar typhimurium invasion genes by csrA}, volume={68}, ISSN={["1098-5522"]}, DOI={10.1128/IAI.68.12.6790-6797.2000}, abstractNote={ABSTRACT}, number={12}, journal={INFECTION AND IMMUNITY}, author={Altier, C and Suyemoto, M and Lawhon, SD}, year={2000}, month={Dec}, pages={6790–6797} }
 @article{altier_suyemoto_1999, title={A recombinase-based selection of differentially expressed bacterial genes}, volume={240}, ISSN={["1879-0038"]}, DOI={10.1016/S0378-1119(99)00427-8}, abstractNote={Bacterial genes are often differentially expressed in response to specific environmental conditions. We have devised a method to identify regulated bacterial promoters, such that transient promoter expression leads to a permanent and selectable change in bacterial phenotype. This system consists of a promoterless derivative of cre, the phage P1 recombinase, carried on a plasmid, and two chromosomal loxP sites, the targets of the Cre recombinase. The loxP sites flank npt, conferring kanamycin resistance, and sacB, which confers sensitivity to sucrose, allowing positive selection for both the presence and absence of this chromosomal cassette. Fusion of active promoters to cre induces recombination of the loxP sites and deletion of intervening DNA, allowing selection on media containing sucrose, while inactive promoters fail to induce recombination and so remain resistant to kanamycin. We tested the system in Salmonella typhimurium using a known regulated promoter, that from the araBAD operon, and found it to be a sensitive indicator of gene expression over a wide range of promoter induction. We then used this system to identify S. typhimurium genes that are specifically expressed when bacteria interact with cultured epithelial cells and identified a novel DNA fragment, not found in E. coli, which might represent part of a new pathogenicity island.}, number={1}, journal={GENE}, author={Altier, C and Suyemoto, M}, year={1999}, month={Nov}, pages={99–106} }
 @article{sellon_walker_suyemoto_altier_1997, title={Nucleic acid amplification for rapid detection of Rhodococcus equi in equine blood and tracheal wash fluids}, volume={58}, number={11}, journal={American Journal of Veterinary Research}, author={Sellon, D. C. and Walker, K. and Suyemoto, M. M. and Altier, C.}, year={1997}, pages={1232–1237} }
 @article{mason_suyemoto_baynes_almond, title={Stability and bioactivity of tetracycline hydrochloride water medication in a swine production unit}, volume={19}, number={2}, journal={Journal of Swine Health and Production}, author={Mason, S. E. and Suyemoto, M. and Baynes, R. and Almond, G.}, pages={107–111} }