Environmental mycobacteria tend to be nonpathogenic but nontuberculous mycobacterium (NTM) infections have become a frequent cause of morbidity and mortality in immunosuppressed patients in recent years. M. mucogenicum, initially considered an environmental bacterium, is possibly evolving into a human pathogen. While the whole genome sequences of M. mucogenicum strains are available on NCBI, there is not much information on its evolution, biology, genetics and virulence. I present the first comparative genome analysis of M. mucogenicum strains. The purpose of this study is to perform a comparative genomics study between M. mucogenicum and other groups of mycobacteria such as slow-growing and pathogenic members (such as M. tuberculosis and M. leprae) and other environmental RGMs in the context of virulence genes, which will enable us to identify the genes that allow M. mucogenicum to be pathogenic and resistant to antibiotics, biocides and other harsh environmental factors.
In this research, we found that 503 novel gene clusters are specific to M. mucogenicum but no other Mycobacterium species. Thus, these genomic regions e.g: Siderophore biosynthesis by non-ribosomal peptide synthetase, oligopeptide transport system etc, likely endow M. mucogenicum with species-specific functions not previously reported. Our result reveals that M. mucogenicum has an open, non-conservative pan-genome structure, indicating a high degree of horizontal gene transfer. The total number of species-specific virulence factor genes was found to be 144. This comparative study will allow a better understanding of M. mucogenicum and provide the basis for future functional work on this important pathogen.