A highly active decarboxylating dehydrogenase with rationally inverted coenzyme specificity.
收藏PubMed Central1995-12-05 更新2026-05-02 收录
下载链接：
https://pmc.ncbi.nlm.nih.gov/articles/PMC40463/
下载链接
链接失效反馈官方服务：
资源简介：
The isocitrate dehydrogenase of Escherichia coli, which lacks the Rossmann fold common to other dehydrogenases, displays a 7000-fold preference for NADP over NAD (calculated as the ratio of kcat/Km). Guided by x-ray crystal structures and molecular modeling, site-directed mutagenesis has been used to introduce six substitutions in the adenosine binding pocket that systematically shift coenzyme preference toward NAD. The engineered enzyme displays an 850-fold preference for NAD over NADP, which exceeds the 140-fold preference displayed by a homologous NAD-dependent enzyme. Of the six mutations introduced, only one is identical in all related NAD-dependent enzyme sequences--strict adherence to homology as a criterion for replacing these amino acids impairs function. Two additional mutations at remote sites improve performance further, resulting in a final mutant enzyme with kinetic characteristics and coenzyme preference comparable to naturally occurring homologous NAD-dependent enzymes. IMAGES:
提供机构：
National Academy of Sciences
创建时间：
1995-12-05
