Physiological roles of mycothiol in detoxification and tolerance to multiple poisonous chemicals in Corynebacterium glutamicum

Abstract

Mycothiol (MSH) plays important roles in maintaining cytosolic redox homeostasis and in adapting to reactive oxygen species in the high-(G + C)-content Gram-positive Actinobacteria. However, its physiological roles are ill defined compared to glutathione, the functional analog of MSH in Gram-negative bacteria and most eukaryotes. In this research, we explored the impact of intracellular MSH on cellular physiology by using MSH-deficient mutants in the model organism Corynebacterium glutamicum. We found that intracellular MSH contributes significantly to resistance to alkylating agents, glyphosate, ethanol, antibiotics, heavy metals and aromatic compounds. In addition, intracellular MSH is beneficial for withstanding oxidative stress induced by various oxidants in C. glutamicum. This study greatly expanded our current knowledge on the physiological functions of mycothiol in C. glutamicum and could be applied to improve the robustness of this scientifically and commercially important species in the future.

NrdH Redoxin Enhances Resistance to Multiple Oxidative Stresses by Acting as a Peroxidase Cofactor in Corynebacterium glutamicum

“…MSH has been reported to play important roles in tolerance to oxidative and acid stresses, antibiotics, aromatic compounds, and heavy metal ions (15)(16)(17)(18). After substantial progress was made in MSH research in the past decade, a lot of efforts have been put on the identification and characterization of novel antioxidant enzymes in Actinobacteria recently.…”

C 1 Metabolism in Corynebacterium glutamicum: an Endogenous Pathway for Oxidation of Methanol to Carbon Dioxide

“…The mycothiol dependence of formaldehyde oxidation by AdhE of C. glutamicum was confirmed by the fact that a mycothiol-defective mutant (⌬mshC) showed the same phenotype as a ⌬adhE mutant and a ⌬ald ⌬mshC double mutant behaved similarly to a ⌬ald ⌬adhE mutant. In C. glutamicum, mycothiol was reported to contribute to resistance to alkylating agents, glyphosate, ethanol, antibiotics, heavy metals, and aromatic compounds (63). Our findings indicate that C. glutamicum, similar to R. erythropolis (47), can oxidize formaldehyde in an MSH-dependent manner via AdhE and in an NAD-dependent manner via Ald.…”

BacHBerry: BACterial Hosts for production of Bioactive phenolics from bERRY fruits

“…C. glutamicum is a very robust microorganism, which shows high resistance to the presence of small aromatic compounds (Liu et al 2013), which renders C. glutamicum a very promising host for the production of pharmacologically interesting plant-derived polyphenols (Marienhagen and Bott 2013). Until recently, the activity of a complex catabolic network for aromatic compounds meant that C. glutamicum was not used for the production of aromatic compounds (except for aromatic amino acids; Shen et al 2012) due to rapid degradation of the products of interest.…”