Mycobacterium tuberculosis, the causative agent of the infectious disease tuberculosis, has a distinct lipid-rich cell wall. Several anti-TB drugs target cell wall biosynthetic pathways. A good understanding of its biosynthesis will provide helpful clues for the development of novel drug targets. A strategy based on random transposon (Tn) mutagenesis with two different screening criteria, altered colony morphology and mycobacteriophage resistance, was developed. Non-pathogenic Mycobacterium smegmatis and the fish pathogen Mycobacterium marinum were used for generating Tn-mutant libraries. From the colony morphology screen, two out of eight genes identified from M. smegmatis Tn-mutants and eleven out of twenty from M. marinum Tn-mutants with altered colony morphology were directly involved in cell wall synthesis. One mutant from each species was chosen for further study, the M. smegmatis 3D9 Tn-mutant with the only isocitrate dehydrogenase (icd) gene disrupted and the M. marinum 8G10 mutant with a Tn inserted into the promoter region of MMAR0978 with a deficiency in methoxymycolates production. Four mutants resistant to generalised transducing phage I3 were identified with a Tn insertion in a gene cluster involved in the biosynthesis of the cell wall associated glycopeptidolipids (GPLs), demonstrating the potential of using phage-resistant mutants for identifying cell wall biosynthetic genes
Is data on this page outdated, violates copyrights or anything else? Report the problem now and we will take corresponding actions after reviewing your request.