Lysis-deficient phages as novel therapeutic agents for controlling bacterial infection

BMC Microbiology

Research Article

Sanjeev Saravanan Rajagopalan¹  Janakiraman Ramachandran¹  Bharathi Sriram¹  Sukumar Hariharan¹  Sudarson Sundarrajan¹  Nanjundappa Kempashanaiah²  Vivek Daniel Paul³  Sriram Padmanabhan⁴ 

[1] Gangagen Biotechnologies Pvt Ltd, No. 12, 5th Cross, Raghavendra Layout, Tumkur Road, 560 022, Yeshwantpur, Bangalore, India;Gangagen Biotechnologies Pvt Ltd, No. 12, 5th Cross, Raghavendra Layout, Tumkur Road, 560 022, Yeshwantpur, Bangalore, India;Department of Animal Husbandry, Veterinary Dispensary, Yediyur, 572142, Kunigal Taluk, Tumkur, India;Gangagen Biotechnologies Pvt Ltd, No. 12, 5th Cross, Raghavendra Layout, Tumkur Road, 560 022, Yeshwantpur, Bangalore, India;Department of Molecular Genetics, University of Toronto, 1 King's College Circle, M5S 1A8, Toronto, ON, Canada;Gangagen Biotechnologies Pvt Ltd, No. 12, 5th Cross, Raghavendra Layout, Tumkur Road, 560 022, Yeshwantpur, Bangalore, India;Lupin Limited, Biotechnology R & D, Gat #1156, Ghotawade Village, 411042, Mulshi Taluka, Pune, India;

关键词: Luria Bertani;    Endolysin;    Phage Therapy;    Temperate Phage;    Recombinant Phage;   

DOI  :  10.1186/1471-2180-11-195

 received in 2011-04-06, accepted in 2011-08-31,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundInterest in phage therapy has grown over the past decade due to the rapid emergence of antibiotic resistance in bacterial pathogens. However, the use of bacteriophages for therapeutic purposes has raised concerns over the potential for immune response, rapid toxin release by the lytic action of phages, and difficulty in dose determination in clinical situations. A phage that kills the target cell but is incapable of host cell lysis would alleviate these concerns without compromising efficacy.ResultsWe developed a recombinant lysis-deficient Staphylococcus aureus phage P954, in which the endolysin gene was rendered nonfunctional by insertional inactivation. P954, a temperate phage, was lysogenized in S. aureus strain RN4220. The native endolysin gene on the prophage was replaced with an endolysin gene disrupted by the chloramphenicol acetyl transferase (cat) gene through homologous recombination using a plasmid construct. Lysogens carrying the recombinant phage were detected by growth in presence of chloramphenicol. Induction of the recombinant prophage did not result in host cell lysis, and the phage progeny were released by cell lysis with glass beads. The recombinant phage retained the endolysin-deficient genotype and formed plaques only when endolysin was supplemented. The host range of the recombinant phage was the same as that of the parent phage. To test the in vivo efficacy of the recombinant endolysin-deficient phage, immunocompromised mice were challenged with pathogenic S. aureus at a dose that results in 80% mortality (LD80). Treatment with the endolysin-deficient phage rescued mice from the fatal S. aureus infection.ConclusionsA recombinant endolysin-deficient staphylococcal phage has been developed that is lethal to methicillin-resistant S. aureus without causing bacterial cell lysis. The phage was able to multiply in lytic mode utilizing a heterologous endolysin expressed from a plasmid in the propagation host. The recombinant phage effectively rescued mice from fatal S. aureus infection. To our knowledge this is the first report of a lysis-deficient staphylococcal phage.

【 授权许可】

Unknown   
© Paul et al; licensee BioMed Central Ltd. 2011. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.