Surface Microstructure and Component Changes of Chromium-resistant Enterobacter Cloacae CYS-25 Strain  

作　　者：马晓艳 杨春鹏 程扬健 栗斌 李冬松 林璋 黄丰 郑晶 

机构地区：[1]State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, The Chinese Academy of Sciences [2]Fuzhu Entry-exit Inspection and Quarantine Bureau

出　　处：《Chinese Journal of Structural Chemistry》2008年第1期15-20,共6页结构化学（英文）

基　　金：This work was supported by the National Natural Science Foundation of China (20501020, 40772034); Nanoscience Foundation of China (90406024);Natural Science Foundation of Fujian Province (No. X0650094/2006J0383);973 program (2007CB815601); the Special Project on Science and Technology of Fujian Province (2005YZ1026)

摘　　要：Enterobacter cloacae CYS-25 strain was isolated from a chromate plant. This bacterium was capable of resisting high hexavalent chromium concentration and reducing Cr（VI） under aerobic condition. CrO4^2- stimulated the increase of bacterial size and production of compact convex paths containing chromium on the bacterial surface. The increase of bacterial size was caused by integrative growth but not extracellular polymeric substance hyperplasia. IR and SDS-PAGE analyses showed the extracellular polymeric substance （EPS） components were mainly proteins and had no obvious changes whether the strains were induced by Cr（VI） or not. The EPS was amorphous and contained trivalent chromium. Under CrO4^2- growth condition, the extracellular substance of Enterobacter cloacae CYS-25 strains and Cr（VI） had redox reaction. The products were Cr^3＊-protein complexes which formed a piece of compact convex paths on the surface of bacteria and prevented Cr（VI） from entering into cells.Enterobacter cloacae CYS-25 strain was isolated from a chromate plant. This bacterium was capable of resisting high hexavalent chromium concentration and reducing Cr（VI） under aerobic condition. CrO4^2- stimulated the increase of bacterial size and production of compact convex paths containing chromium on the bacterial surface. The increase of bacterial size was caused by integrative growth but not extracellular polymeric substance hyperplasia. IR and SDS-PAGE analyses showed the extracellular polymeric substance （EPS） components were mainly proteins and had no obvious changes whether the strains were induced by Cr（VI） or not. The EPS was amorphous and contained trivalent chromium. Under CrO4^2- growth condition, the extracellular substance of Enterobacter cloacae CYS-25 strains and Cr（VI） had redox reaction. The products were Cr^3＊-protein complexes which formed a piece of compact convex paths on the surface of bacteria and prevented Cr（VI） from entering into cells.

关 键 词：Enterobacter cloacae chromium-resistance extracellular polymeric substance（EPS） 

分 类 号：O611.3[理学—无机化学]