Construction of lipF anti-sense knock out mutant of Mycobacterium fortuitum and study of its role in in-vivo infection and virulence

Abstract

Tuberculosis can be considered as one of the major causes of deaths throughout the world. In order to identify the genes required for the pathogenicity of Mycobacterium tuberculosis, a functional genomic approach has been developed. Also, these hospital acquired outbursts caused by the mycobacteria are in the picture of medical sciences for more than 20 years, yet to be diminished. Most of these outbreaks have involved the rapidly growing mycobacterial species. Among these mycobacterial species, tuberculosis is considered as the major factor of most of the deaths worldwide due to a single pathogen involved, Mycobacterium tuberculosis. Another important species in this respect belonging to the same taxon includes Mycobacterium fortuitum which is a non-tuberculous mycobacterium (NTM) causing various clinical symptoms such as cutaneous infections, respiratory infections, joint infections and disseminated infections in immuno-compromised patients. Out of the all the genes identified for the virulence of this pervasive disease, lipF has played a major role whose significance hasn’t been taken into consideration by many researchers as such. This gene coding for lipid esterase, expresses well for the virulence of tuberculosis and, is regulated by PhoP. lipF implicates modification of the mycobacterial cell wall as an adaptive response to acid damage, also degrades host lipids during infection, making fatty acids available as building blocks for lipid biosynthesis. Gene helps in compensating with all the un-favorable acidic conditions in macrophages, where mycobacterium resides. This project mainly aims on the construction of lipF anti-sense knock out mutant by taking Mycobacterium fortuitum as the base model to check its role in virulence of tuberculosis as the homology between the genomic sequences (M. fortuitum and M. tuberculosis) of the two was found to be 67%