Seyed E. Hasnain of the Institute of Life Sciences (ILS) says that both the MIP and the MAP bacilli initially inhabited water bodies, and infected marine organisms predated by fishes. They arrived on soil through bird-droppings, he adds.
The MIP bacilli were first isolated in India by G. P. Talwar at the All India Institute of Medical Sciences, New Delhi, in the Eighties. It is now used as an immunotherapeutic against leprosy in the country.
The success with MIP based leprosy vaccine has led to human clinical evaluations of MIP in interventions against HIV-AIDS, psoriasis and bladder cancer in India.
It is commercially available as 'Immuvac', and is currently the focus of advanced multi-centric phase III clinical trials for its anti-tuberculosis efficacy.
The findings, published in the open access journal PLoS ONE, are based on a study of complete sequence of the MIP organism, which is the first ever whole-genome-sequencing project from India.
The project was carried out jointly by the ILS, the Centre for DNA fingerprinting and Diagnostics also at Hyderabad and the University of Delhi.
According to the researchers, their findings provide an important evolutionary basis for the acquisition and optimisation of virulence in mycobacteria and determinants of boundaries therein.
The study provides new insight into the role of non-pathogenic and saprophytic mycobacteria in immunomodulation, and in triggering innate immune responses. It also advocates exploitation of genetic similarity between MIP and MAP as a plausible advantage for therapeutic intervention against Crohn's disease in humans and Johne's disease in cattle