@article{madsen_mills_djordjevic_israelsen_klaenhammer_2001, title={Analysis of the genetic switch and replication region of a P335-type bacteriophage with an obligate lytic lifestyle on Lactococcus lactis}, volume={67}, ISSN={["1098-5336"]}, DOI={10.1128/AEM.67.3.1128-1139.2001}, abstractNote={ABSTRACT}, number={3}, journal={APPLIED AND ENVIRONMENTAL MICROBIOLOGY}, author={Madsen, SM and Mills, D and Djordjevic, G and Israelsen, H and Klaenhammer, TR}, year={2001}, month={Mar}, pages={1128–1139} } @misc{klaenhammer_conkling_o'sullivan_djordjevic_walker_taylor_1998, title={Bacteriophage-triggered cell suicide systems and fermentation methods employing the same}, volume={5,792,625}, number={1998 Aug. 11}, publisher={Washington, DC: U.S. Patent and Trademark Office}, author={Klaenhammer, T. R. and Conkling, M. A. and O'Sullivan, D. and Djordjevic, G. and Walker, S. A. and Taylor, C. G.}, year={1998} } @misc{djordjevic_klaenhammer_1998, title={Inducible gene expression systems in Lactococcus lactis}, volume={9}, ISSN={["1073-6085"]}, DOI={10.1007/BF02760814}, abstractNote={Lactococcus lactis is industrially important microorganism used in many dairy fermentations. Numerous genes and gene expression signals from this organism have now been identified and characterized. Recently, several naturally occurring, inducible gene-expression systems have also been described in L. lactis. The main features of these systems can be exploited to design genetically engineered expression cassettes for controlled production of various proteins and enzymes. Novel gene-expression systems in Lactococcus have great potential for development of industrial cultures with desirable metabolic traits for a variety of bioprocessing applications.}, number={2}, journal={MOLECULAR BIOTECHNOLOGY}, author={Djordjevic, GM and Klaenhammer, TR}, year={1998}, month={Apr}, pages={127–139} } @article{djordjevic_osullivan_walker_conkling_klaenhammer_1997, title={A triggered-suicide system designed as a defense against bacteriophages}, volume={179}, ISSN={["0021-9193"]}, DOI={10.1128/jb.179.21.6741-6748.1997}, abstractNote={A novel bacteriophage protection system for Lactococcus lactis based on a genetic trap, in which a strictly phage-inducible promoter isolated from the lytic phage phi31 is used to activate a bacterial suicide system after infection, was developed. The lethal gene of the suicide system consists of the three-gene restriction cassette LlaIR+, which is lethal across a wide range of gram-positive bacteria. The phage-inducible trigger promoter (phi31P) and the LlaIR+ restriction cassette were cloned in Escherichia coli on a high-copy-number replicon to generate pTRK414H. Restriction activity was not apparent in E. coli or L. lactis prior to phage infection. In phage challenges of L. lactis(pTRK414H) with phi31, the efficiency of plaquing was lowered to 10(-4) and accompanied by a fourfold reduction in burst size. Center-of-infection assays revealed that only 15% of infected cells released progeny phage. In addition to phage phi31, the phi31P/LlaIR+ suicide cassette also inhibited four phi31-derived recombinant phages at levels at least 10-fold greater than that of phi31. The phi31P/LlaIR+-based suicide system is a genetically engineered form of abortive infection that traps and eliminates phages potentially evolving in fermentation environments by destroying the phage genome and killing the propagation host. This type of phage-triggered suicide system could be designed for any bacterium-phage combination, given a universal lethal gene and an inducible promoter which is triggered by the infecting bacteriophage.}, number={21}, journal={JOURNAL OF BACTERIOLOGY}, author={Djordjevic, GM and OSullivan, DJ and Walker, SA and Conkling, MA and Klaenhammer, TR}, year={1997}, month={Nov}, pages={6741–6748} } @article{djordjevic_klaenhammer_1997, title={Bacteriophage-triggered defense systems: Phage adaptation and design improvements}, volume={63}, number={11}, journal={Applied and Environmental Microbiology}, author={Djordjevic, G. M. and Klaenhammer, T. R.}, year={1997}, pages={4370–4376} } @misc{djordjevic_klaenhammer_1997, title={Genes and gene expression in Lactococcus bacteriophages}, volume={7}, ISSN={["0958-6946"]}, DOI={10.1016/S0958-6946(97)00060-5}, abstractNote={Lactococcus lactis is extensively used in the production of cheese and cultured dairy products in industrial fermentations worldwide. Bacteriophage infection of L. lactis imposes a constant threat to the fermentation industry and represents the major cause of fermentation failure. Numerous phage defense strategies have been developed over the years to protect industrial starter cultures, particularly L. lactis. Numerous genes from lactococcal bacteriophages have been cloned and characterized and mechanisms that regulate their expression elucidated. Complete genome sequences of several L. lactis bacteriophages have also been determined. This accumulation of genetic information on lactococcal bacteriophages has led to a better understanding of the phage life cycle, host interactions, relationships between lactococcal phages, and possible patterns of phage evolution. These advances in molecular biology of lactococcal bacteriophages will be discussed with a view towards the development of novel and more effective phage defenses.}, number={8-9}, journal={INTERNATIONAL DAIRY JOURNAL}, author={Djordjevic, GM and Klaenhammer, TR}, year={1997}, pages={489–508} }