微生物的2,3-丁二醇（BD）代谢对与其共生的动物、植物、微生物的生理代谢过程有着重要的影响。相对于BD的合成机制，微生物的BD分解代谢机制仍有多个关键步骤未能阐明，限制了BD代谢相关生理过程研究的开展。环境微生物模式菌株Pseudomonas putida KT2440可同时利用BD的3种异构体为唯一碳源生长。本项目拟以P. putida KT2440为研究对象，分析该菌株中3种2,3-丁二醇脱氢酶分别在3种BD异构体脱氢生成乙偶姻过程中的作用；揭示乙偶姻脱氢酶催化乙偶姻脱氢裂解的具体机制；蛋白分离纯化与转录组学技术确定乙偶姻消旋酶编码基因，阐明乙偶姻消旋酶参与2种乙偶姻互变及BD代谢的内在机理；转录组学与关键基因敲除及回补相结合，解析乙偶姻裂解产物下游代谢途径，分析BD利用对其它生理过程相关基因转录的影响。该项目可为深入揭示微生物BD分解代谢机制及相关生理过程奠定理论基础。

Microbial 2,3-butanediol (BD) metabolism have a significant impact on physiological processes of its symbiotic animals, plants, microorganisms. However, different from the BD synthesis mechanism, there are still several unclear key steps in microbial catabolism of BD, which limits the investigation of BD metabolism-related physiological processes. Pseudomonas putida KT2440 is a model strain of environmental microorganism. It can simultaneously use the three isomers of BD as the sole carbon source. In this project, P. putida KT2440 would be used as the research object for the study of BD catabolism. Roles of the three kinds of 2,3-butanediol dehydrogenase in production of acetoin from the three isomers of BD would be identified, respectively. Mechanisms of the dehydrogenation and splitting of acetoin by the acetoin dehydrogenase would be clarified. Based on the protein purification and transcriptomics techniques, the acetoin racemase encoding gene and its roles in interconversion of the two kinds of acetoin and BD utilization would be determined. Transcriptome would also be used in the project to determine the downstream metabolic pathways of acetoin lysates and to analyze the gene transcription of other physiological processes related to BD utilization. Based on the result of the project, the theoretical basis for the deeply revealing of the microbial BD metabolism mechanism and related physiological process would be established.