Tietao Wang, Fen Gao , Yiwen Kang , Chao Zhao , Tao Su , Muhang Li , Meiru Si , Xihui Shen Mycothiol peroxidase MPx protects Corynebacterium glutamicum against acid stress by scavenging ROS

Mycothiol peroxidase MPx protects Corynebacteriumglutamicum against acid stress by scavenging ROS

Tietao Wang, Fen Gao , Yiwen Kang , Chao Zhao , Tao Su , Muhang Li , Meiru Si , Xihui Shen

Biotechnol Lett 

DOI:10.1007/s10529-016-2099-y

Abstract: Objectives To investigate mycothiol peroxidase (MPx) of Corynebacterium glutamicum that is a novel CysGPx family peroxidase using both the mycore-doxin and thioredoxin reducing systems as proton donors for peroxide detoxification and may be involved in the relief of acid stress. Results A Dmpx mutant exhibited significantly decreased resistance to acid stress and markedly increased accumulation of reactive oxygen species (ROS) and protein carbonylation levels in vivo. Over-expression of mpx increased the resistance of C. glutamicum to acid stress by reducing ROS accumulation. The stress-responsive extracytoplasmic function-sigma (ECF-r) factor, SigH, mediated acid-induced expression of mpx in the wild-type under acid conditions, which in turn directly contributed to tolerance to acid stress. Conclusion MPx is essential for combating acid stress by reducing intracellular ROS levels induced by  Acid stress in C.glutamicum,which adds a new dimension to the general physiological functions of CysGPx.