Enzymatic Investigations in Gentamicin C Biosynthesis

主题：工业生物技术和生物能源后抗生素时代的必然途径将注意力集中在现有抗菌剂的改造上，以获得更强大的变种。重组天然产物衍生抗生素的生物合成途径是替代半合成方法的一种有吸引力的替代方法，其前提是认识完整的生物合成酶。本项目将通过使用底物类似物的功能酶研究，努力探索参与庆大霉素生物合成中独特的3‘，4’-双脱羟基过程的氨基转移酶GenB1、GenB2、GenB3和GenB4的底物特异性。这将使人们能够努力合理地操纵酶转化，这是改变生物合成途径的路线以获得确定的最终产品组成的任务的先决条件。同样，需要对脱氢酶GenQ的底物专一性进行工程，以促进这一目标的实现。以前关于JI-20B/JI20BA同分异构体对的研究--关于手性C-6位构型的确定--也将结束。

Theme: Industrial Biotechnology and BioenergyThe inevitable approach of the post-antibiotic era has focussed attention on the revamp of established antibacterial agents in order to attain more robust variants. Re-engineering the biosynthetic pathway of a natural product-derived antibiotic is an attractive alternative to semisynthetic approaches; a prerequisite for this is cognizance of the complete biosyntheticenzymology.This project will endeavour to explore the substrate specificity of the aminotransferases GenB1, GenB2, GenB3 and GenB4involved in the distinctive 3',4'-bisdehydroxylation process in gentamicin biosynthesis, by functional enzyme studies usingsubstrate analogs. This would enable efforts to rationally manipulate the enzymatic transformations which is a prerequisitefor the task of redirecting the course of the biosynthetic pathway to obtain a defined composition of end-product. Likewise, engineering the substrate specificity of the dehydrogenase GenQ will need to be undertaken to contribute to the accomplishment of such an aim. Previous studies concerning the JI-20B/JI20Ba epimer pair - on the determination of configuration at the chiral C-6 position - will also be concluded.