还原型谷胱甘肽调控shewanella oneidensis MR-1降解亚碲酸盐

探讨了生物活性小分子还原型谷胱甘肽（GSH）调控奥奈达湖希瓦氏菌（shewanella oneidensis）MR-1还原亚碲酸盐的特性及机理.结果表明，生物体系中加入0.1，0.4，1.0mmol/L GSH，与空白对照相比，亚碲酸盐的生物还原效率可分别提高55%、71%和78%，且GSH浓度在0.1~1.0mmol/L范围内与亚碲酸盐的生物还原效率呈正相关.采用单因素实验优化了培养条件，在温度35℃，pH 8.0，GSH浓度为0.4mmol/L的条件下，亚碲酸盐生物还原效率在24h内即可达到97%.采用6种不同呼吸抑制剂实验探讨亚碲酸盐生物还原的电子传递路径，确定GSH在亚碲酸盐生物还原电子传递链上的加速位点为NADH还原酶、甲萘醌和FAD脱氢酶.

The regulated characteristics and mechanism of tellurite bioreduction by reduced glutathione (GSH) with Shewanella oneidensis MR-1.

The regulated characteristics and mechanism of tellurite bioreduction by bioactive small molecule glutathione (GSH) with Shewanella oneidensis MR-1 were investigated in this study. When 0.1, 0.4 and 1.0mmol/L GSH were added to the bioreduction system, the bioreduction efficiency of the tellurite was increased by 55%, 71% and 78%, respectively, compared with the control. Moreover, the concentration of GSH (0.1~1.0mmol/L) was positively correlated with the bioreduction efficiency of tellurite. The culture conditions were optimized by single factor experiment. Under the conditions of 35℃, pH 8.0, 0.4mmol/L GSH, the bioreduction efficiency of tellurite reached 97% within 24h. In addition, six different respiratory inhibitors were used to investigate the regulated electron transfer pathway of tellurite bioreduction by GSH. It was preliminarily determined that the accelerating sites of GSH in the electron transfer chain were NADH reductase, methylnaphthoquinone and FAD dehydrogenase.