%0 Journal Article %A Ng, Hien Fuh %A Tan, Joon Liang %A Zin, Thaw %A Yap, Sook Fan %A Ngeow, Yun Fong %T A mutation in anti-sigma factor MAB_3542c may be responsible for tigecycline resistance in Mycobacterium abscessus %D 2018 %J Journal of Medical Microbiology, %V 67 %N 12 %P 1676-1681 %@ 1473-5644 %R https://doi.org/10.1099/jmm.0.000857 %K anti-sigma factor %K MAB_3542c %K RshA %K tigecycline resistance %K Mycobacterium abscessus %I Microbiology Society, %X 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. %U https://www.microbiologyresearch.org/content/journal/jmm/10.1099/jmm.0.000857