Critical Minireview: The Fate of tRNA^Cysduring Oxidative Stress in <em>Bacillus subtilis</em>

Abstract

Abstract:Oxidative stress occurs when cells are exposed to elevated levels of reactive oxygen species that can damage biological molecules. One bacterial response to oxidative stress involves disulfide bond formation either between protein thiols or between protein thiols and low-molecular-weight (LMW) thiols. Bacillithiol was recently identified as a major low-molecular-weight thiol in Bacillus subtilis and related Firmicutes. Four genes (bshA, bshB1, bshB2, and bshC) are involved in bacillithiol biosynthesis. The bshA and bshB1 genes are part of a seven-gene operon (ypjD), which includes the essential gene cca, encoding CCA-tRNA nucleotidyltransferase. The inclusion of cca in the operon containing bacillithiol biosynthetic genes suggests that the integrity of the 3 terminus of tRNAs may also be important in oxidative stress. The addition of the 3 terminal CCA sequence by CCA-tRNA nucleotidyltransferase to give rise to a mature tRNA and functional molecules ready for aminoacylation plays an essential role during translation and expression of the genetic code. Any defects in these processes, such as the accumulation of shorter and defective tRNAs under oxidative stress, might exert a deleterious effect on cells. This review summarizes the physiological link between tRNA Cys regulation and oxidative stress in Bacillus.

Effect of ginger (Zingiber officinale) on semen quality

“…Ginger rhizome is very rich with various powerful antioxidant compounds such as zingerone, gingerols (e.g., 6‐gingerol, 8‐gingerol, 10‐gingerol), glucosides‐6‐gingerdiol, zingiberene, shogaols (e.g., 4‐shogaol, 6‐shogaol, 8‐shogaol, 3‐dihydroshogaols, methyl [6]‐ and methyl [8]‐shogaol), paradols and dihydroparadols (Ali et al, ; An et al, ; Si, Chen, Zhang, Chen, & Chung, ). Such bioactive antioxidants protect against oxidative stress, an imbalance between oxidants, mainly reactive oxygen species (Hani & Bayachou, ), antioxidants to the favour of the former (Banihani, ), and lipid peroxidation‐induced damage (Banihani, ; Campos Guillen et al, ). Indeed, ginger was found to increase the activity of the antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) in different male reproductive tissues/organs, mainly epididymis, testis and prostate (Ghlissi et al, ).…”