A high yielding mutant of mycobacteriophage L1 and its application as a diagnostic tool

• Published in: FEMS microbiology letters Vol. 188; no. 1; pp. 47 - 53
• Main Authors: Chatterjee, Shreyasi, Mitra, Mahasweta, Das Gupta, Sujoy Kr
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.07.2000; Blackwell; Oxford University Press
• Subjects: Adsorption; Biological and medical sciences; Burst size; Colony Count, Microbial; Deoxyribonucleic acid; Diagnostic software; Diagnostic systems; DNA; DNA, Viral - analysis; Fundamental and applied biological sciences. Psychology; Genetic engineering; Lysogeny; Microbiology; Mutation; Mycobacteriophages - genetics; Mycobacteriophages - growth & development; Mycobacterium; Mycobacterium smegmatis - growth & development; Mycobacterium smegmatis - isolation & purification; Mycobacterium smegmatis - virology; Mycobacterium tuberculosis - growth & development; Mycobacterium tuberculosis - isolation & purification; Mycobacterium tuberculosis - virology; Phages; Restriction Mapping; System effectiveness; Techniques used in virology; Tuberculosis; Viral Plaque Assay; Virology; Mycobacterium; Burst size; Tuberculosis; Mycobacterial infection; Method; Infection; Virus; Characterization; Mycobacteriales; DNA; Bacteriosis; Mycobacteriaceae; Deletion; Bacteria; Actinomycetes; Diagnosis; Mutation; Phage
• ISSN: 0378-1097; 1574-6968
• DOI: 10.1111/j.1574-6968.2000.tb09167.x

Abstract L1 is a lysogenic phage of mycobacteria, which along with L5 and D29 constitute a closely linked family of homoimmune mycobacteriophages. These phages can be potentially used for genetic engineering of mycobacteria and diagnosis of mycobacterial infection. The effectiveness of such phage based systems depends on the efficiency with which they infect and grow within target cells. While working with phage L1c1ts which is a temperature sensitive mutant of phage L1, we observed that high yielding phage stocks were generated by repeated passage through the host, Mycobacterium smegmatis. A plaque purified mutant L1-P2, obtained from one such high yielding stock, when analyzed further was found to infect host cells with increased efficiency. The DNA obtained from L1-P2 was examined by restriction digestion, and it was observed that spontaneous loss of DNA fragment from the right arm, which encodes early regulatory factors, had occurred. It has been further demonstrated that the high yielding property of the mutant phage could be utilized to increase the sensitivity of mycobacteriophage-based detection systems.