title: Mycothiol protects Corynebacterium glutamicum against acid stress via maintaining intracellular pH homeostasis, scavenging ROS, and S-mycothiolating MetE.
abstract: Mycothiol (MSH) plays a major role in protecting cells against oxidative stress and detoxification from a broad range of exogenous toxic agents. In the present study, we reveal that intracellular MSH contributes significantly to the adaptation to acidic conditions in the model organism Corynebacterium glutamicum. We present evidence that MSH confers C. glutamicum with the ability to adapt to acidic conditions by maintaining pHi homeostasis, scavenging reactive oxygen species (ROS), and protecting methionine synthesis by the S-mycothiolation modification of methionine synthase (MetE). The role of MSH in acid adaptation was further confirmed by improving the acid tolerance of C. glutamicum by overexpressing the key MSH synthesis gene mshA. Hence, our work provides insights into a previously unknown, but important, aspect of the C. glutamicum cellular response to acid stress. The results reported here may help to understand acid tolerance mechanisms in acid sensitive bacteria and may open a new avenue for improving acid resistance in industry strains for the production of bio-based chemicals from renewable biomass.
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas and College of Life Sciences, Northwest A&F University.
authors.forename: Yingbao
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Yang
authors.forename: Yajie
authors.initials: Y
authors.lastname: Yin
authors.forename: Jinshui
authors.initials: J
authors.lastname: Lin
authors.forename: Can
authors.initials: C
authors.lastname: Chen
authors.forename: Junfeng
authors.initials: J
authors.lastname: Pan
authors.forename: Meiru
authors.initials: M
authors.lastname: Si
authors.forename: Xihui
authors.initials: X
authors.lastname: Shen
mesh_terms: D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D048230:Corynebacterium glutamicum / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D003545:Cysteine / Q000378:metabolism* / Q000494:pharmacology; D006020:Glycopeptides / Q000378:metabolism* / Q000494:pharmacology; D006706:Homeostasis; D006863:Hydrogen-Ion Concentration; D007294:Inositol / Q000378:metabolism* / Q000494:pharmacology; D008715:Methionine / Q000096:biosynthesis; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism; D013312:Stress, Physiological
chemical_list: D001426:Bacterial Proteins; D006020:Glycopeptides; D017382:Reactive Oxygen Species; D011994:Recombinant Proteins; C089265:mycothiol; D007294:Inositol; D008715:Methionine; D010088:Oxidoreductases; C121837:mycothione reductase; D013766:5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase; D003545:Cysteine