A mutation in anti-sigma factor MAB_3542c may be responsible for tigecycline resistance in Mycobacterium abscessus Ng, Hien Fuh and Tan, Joon Liang and Zin, Thaw and Yap, Sook Fan and Ngeow, Yun Fong,, 67, 1676-1681 (2018), doi = https://doi.org/10.1099/jmm.0.000857, publicationName = Microbiology Society, issn = 0022-2615, abstract= In this study, we characterized 7C, a spontaneous mutant selected from tigecycline-susceptible Mycobacterium abscessus ATCC 19977. Whole-genome sequencing (WGS) was used to identify possible resistance determinants in this mutant. Compared to the wild-type, 7C demonstrated resistance to tigecycline as well as cross-resistance to imipenem, and had a slightly retarded growth rate. WGS and subsequent biological verifications showed that these phenotypes were caused by a point mutation in MAB_3542c, which encodes an RshA-like protein. In Mycobacterium tuberculosis, RshA is an anti-sigma factor that negatively regulates the heat/oxidative stress response mechanisms. The MAB_3542c mutation may represent a novel determinant of tigecycline resistance. We hypothesize that this mutation may dysregulate the stress-response pathways which have been shown to be linked to antibiotic resistance in previous studies., language=, type=