Mycobacterium tuberculosis uvrC essentiality in response to UV-induced cell damage.

Control of tuberculosis depends both on an effective, accurate, and rapid diagnosis and an effective treatment and management. Antituberculous drugs have been used for more than 50 years and are likely ineffective against multidrug-resistant strains, leading to an urgent need for new drugs. Comparative genome analysis has indicated that Mycobacterium tuberculosis uvrC, a component of nucleotide excision repair (NER) system, is an essential gene without any human homolog. This raises the possibility to use this gene as a new drug target. This study investigated the essential role of uvrC on growth of M. tuberculosis in the presence of DNA damaging agents, UV light and hydrogen peroxide (generator of reactive oxygen species). Results revealed that the M. tuberculosis uvrC mutant was more sensitive to UV than the control strain (p < 0.01), but was not more sensitive to hydrogen peroxide. These results showed that uvrC is essential for M. tuberculosis DNA repair system, particularly in response to DNA damage caused by UV irradiation.