中国希瓦氏菌D14^T的厌氧腐殖质呼吸

实验证明,希瓦氏菌新种(ShewanellacinicaD14T)在厌氧条件下可以利用多种有机酸盐和甲苯等环境有毒污染物作为电子供体,以腐殖质作为唯一末端电子受体进行厌氧呼吸(即醌呼吸)。电子在细胞膜呼吸链的传递过程中,偶联能量的产生来支持菌体的生长,1mmol/LAQDS可支持细胞增殖约60倍。电子供体的氧化和唯一电子受体腐殖质还原之间存在着动态的偶联过程,随着电子供体量的增加腐殖质还原的量也随之增加。典型呼吸链抑制剂诸如:抑制Fe-S中心的Cu2 ,甲基萘醌类似物标桩菌素,抑制甲基萘醌氧化型向还原型转化的双香豆素和细胞色素P450的专一抑制物甲吡酮等对腐殖质的还原有着极为显著的抑制作用,为进一步证明希瓦氏菌(Shewanellacinica)D14T可利用腐殖质进行厌氧呼吸提供了有力的佐证。而D14T在进行腐殖质呼吸的同时,对于甲苯,苯胺等环境有毒物质的有效降解则具有着重要的环境学意义。

Anaerobic humus respiration by Shewanella cinica D14^T

Experimental results suggested Shewanella cinica D14~T is capable of humus respiration utilizing various organic acids and some important environmental pollutants (e.g., toluene. etc) as electron donors and AQS or AQDS as a sole terminal electron acceptor under anaerobic condition. The dissimilatory reduction of 1mmol/L AQDS can couple to the production of enough ATP to support cell growth about 60 generations; The oxidization of electron donors was coupled to the reduction of humus, as reduced humus increased corresponding with increasing of electron donor; The typical inhibitors such as Cu~ 2 which inhibited Fe-S center, Stigmatellin which was methyl-naphthoquinone model, Dicumarol which inhibited oxidized methyl-naphthoquinone transform to reduced one, Metyrapone which was specific inhibitor for P450 enzyme blocked the humus respiration seriously. These were powerful evidences for humus-respiration by D14~T.