type	Journal Article
authors	Zhu Y, Xu J, Mei X, Feng Z, Zhang L, Zhang Q, Zhang G, Zhu W, Liu J, Zhang C.
title	Biochemical and Structural Insights into the Aminotransferase CrmG in Caerulomycin Biosynthesis.
journal	ACS Chem Biol.
Activity	crmg
Family	crmg
sel	selected
ui	26714051
year	(2016)
volume	11
number	4
pages	943-52
abstract	Caerulomycin A (CRM A 1) belongs to a family of natural products containing a 2,2'-bipyridyl ring core structure and is currently under development as a potent novel immunosuppressive agent. Herein, we report the functional characterization, kinetic analysis, substrate specificity, and structure insights of an aminotransferase CrmG in 1 biosynthesis. The aminotransferase CrmG was confirmed to catalyze a key transamination reaction to convert an aldehyde group to an amino group in the 1 biosynthetic pathway, preferring l-glutamate and l-glutamine as the amino donor substrates. The crystal structures of CrmG in complex with the cofactor 5'-pyridoxal phosphate (PLP) or 5'-pyridoxamine phosphate (PMP) or the acceptor substrate were determined to adopt a canonical fold-type I of PLP-dependent enzymes with a unique small additional domain. The structure guided site-directed mutagenesis identified key amino acid residues for substrate binding and catalytic activities, thus providing insights into the transamination mechanism of CrmG.
last changed	2019/03/25 14:15