Query: NC_008146:1016446 Mycobacterium sp. MCS, complete genome
Lineage: Mycobacterium; Mycobacterium; Mycobacteriaceae; Actinomycetales; Actinobacteria; Bacteria
General Information: Mycobacterium MCS was isolated from soil in a wood preservative-contaminated land-treatment unit where remediation of polycyclic aromatic hydrocarbon (PAH) was occurring. This isolate mineralizes small- and large-ring PAHs, in contrast to other PAH-degrading microbes. Bioremediation of PAHs offers an attractive solution to pollution clean-up because it can occur on site and at relative little cost compared to alternatives. This isolate belongs to a fast-growing group of the mycobacterium genus that is defined as Gram-positive, acid-fast, pleomorphic, non-motile rods. Bioremediation of soils contaminated with wood preservatives containing polycyclic aromatic hydrocarbons (PAHs) is desired because of their toxic, mutagenic, and carcinogenic properties. Creosote wood preservative–contaminated soils at the Champion International Superfund Site in Libby, Montana currently undergo bioremediation in a prepared-bed land treatment unit (LTU) process.
Subject: NC_015848:1708176 Mycobacterium canettii CIPT 140010059, complete genome
Lineage: Mycobacterium canettii; Mycobacterium; Mycobacteriaceae; Actinomycetales; Actinobacteria; Bacteria
General Information: The Republic of Djibouti, Africa appears to be an exceptional place in terms of tuberculosis (TB) caused by Mycobacterium canettii, a highly unusual tubercle bacillus with unusual smooth colony morphology (STB) related to the M. tuberculosis complex (MTBC). M. canettii was first isolated from a 20-year-old French farmer suffering from pulmonary tuberculosis by G. Canetti in 1969. Since then, this strain has been isolated on rare occasions from patients who lived or were presumably infected in East Africa. It tends to preferentially affect children and foreigners in the Horn of Africa. M. canettii, a possible ancestor of the MTBC, is found almost exclusively in the Horn of Africa where TB is thought to have emerged about 40 000 years ago, coinciding with the expansion of human population out of Africa. The geographical restriction of M. canettii isolates and contrasting genetic diversity are characteristics compatible with a non-human reservoir. With the larger pan-genome reflecting the ancestral, wider gene pool of tubercle bacilli, their lower virulence and faster growth, especially at temperatures below 37 degrees C, plausibly reflecting broader environmental adaptability, STB strains might thus come nearer to the as-yet-unknown missing link between the obligate pathogen M. tuberculosis and environmental mycobacteria (adapted from PMIDs 20831613 and 23291586). Mycobacteria have an unusual outer membrane approximately 8nm thick, despite being considered Gram-positive. The outer membrane and the mycolic acid-arabinoglactan-peptidoglycan polymer form the cell wall, which constitutes an efficient permeability barrier in conjunction with the cell inner membrane.