There are currently two narratives existing in parallel regarding the age of MTBC and how it has spread and co-evolved with humans through time. tuberculosis phylogeny to a human mitochondrial genome phylogeny and interpreted these as being highly similar. tuberculosis, like humans, evolved in Africa and subsequently spread with anatomically modern humans out of Africa across the world. tuberculosis to match this narrative, the study suggested that MTBC evolved 40,000 – 70,000 years ago.Applying this time scale, the study found that the M.tuberculosis can appear either Gram-negative or Gram-positive. tuberculosis is highly aerobic and requires high levels of oxygen. tuberculosis can be spread by shaking hands, making contact with toilet seats, sharing food or drink, sharing toothbrushes, or kissing.
This has now been superseded by variable numbers of tandem repeats (VNTR), which is technically easier to perform and allows better discrimination between strains. This provides a degree of resolution greater than PFGE and is currently the standard for typing M. Its size is 4 million base pairs, with 3,959 genes; 40% of these genes have had their function characterised, with possible function postulated for another 44%. The genome contains 250 genes involved in fatty acid metabolism, with 39 of these involved in the polyketide metabolism generating the waxy coat. The main human-infecting species have been classified into seven lineages.
These proteins have a conserved N-terminal motif, deletion of which impairs growth in macrophages and granulomas. Lineage 3 has been divided into two clades: CAS-Kili (found in Tanzania) and CAS-Delhi (found in India and Saudi Arabia).
In 2013, a study on the genome of several sensitive, ultraresistant, and multiresistant M. Lineage 4 is also known as the Euro-American lineage.
Noteworthy is the role of the intergenic regions in the development of this resistance, and most of the genes proposed in this study to be responsible for drug resistance have an essential role in the development of M. However, a later study that included genome sequences from M.
tuberculosis complex members extracted from three 1,000 year old Peruvian mummies, came to quite different conclusions. tuberculosis complex were 40,000 to 70,000 years old, this would necessitates an evolutionary rate much lower than any estimates produced by genomic analyses of heterochronous samples.
Granulotomatous lesions are important in both regulating the immune response and minimizing tissue damage.