报告题目：Structure and function of azoreductase from human commensal microbiota 

　　报 告 人：CHEN Huizhong （美国FDA国家毒理学研究中心 微生物学家） 

　　报告时间：9月24日（周三）10：00-11:30

　　报告地点：中国科学院天津工业生物技术研究所 C408会议室

　　报告摘要：Approximately 0.7 million tons of azo dyes are synthesized each year.  Azo dyes are composed of one or more R₁-N=N-R₂ linkages. Studies have shown that both mammalian and microbial azoreductases cleave the azo bonds of the dyes to form compounds that are potentially genotoxic. The human gastrointestinal tract harbors a diverse microbiota comprised of thousand species. Both water-soluble and water-insoluble azo dyes can be reduced by intestinal bacteria. Some of the metabolites produced by intestinal microbiota have been shown to be carcinogenic to humans although the parent azo dyes may not be classified as being carcinogenic. Azoreductase activity is commonly found in intestinal bacteria. Three types of azoreductases have been characterized in bacteria. They are flavin dependent NADH preferred azoreductase, flavin dependent NADPH preferred azoreductase, and flavin free NADPH preferred azoreductase.  This presentation will highlight how azo dyes are metabolized by intestinal bacteria, mechanisms of azo reduction, structure and function of azoreductase, and the potential contribution in the carcinogenesis/mutagenesis of the reduction of the azo dyes by intestinal microbiota.

　　报告人简介：CHEN Huizhong，山东大学微生物系博士。现任美国食品药品监督管理局国家毒理学研究中心微生物学家，GS-15（等同于终身教授）、暨南大学兼职教授、阿肯色大学应用科学系研究生导师。曾任Aureozyme公司资深科学家，Georgia大学生物化学与分子生物学系博士后、助教，山东大学微生物系助教，奥地利Graz大学生物化学系访问学者。