59862-05-4Relevant academic research and scientific papers
A mechanistic study of the non-oxidative decarboxylation catalyzed by the radical S-adenosyl-l-methionine enzyme BlsE involved in blasticidin S biosynthesis
Liu, Lei,Ji, Xinjian,Li, Yongzhen,Ji, Wenjuan,Mo, Tianlu,Ding, Wei,Zhang, Qi
supporting information, p. 8952 - 8955 (2017/08/15)
Decarboxylation is a fundamentally important reaction in biology and involves highly diverse mechanisms. Here we report a mechanistic study of the non-oxidative decarboxylation catalyzed by BlsE, a radical S-adenosyl-l-methionine (SAM) enzyme involved in blasticidin S biosynthesis. Through a series of biochemical analysis with isotopically labeled reagents, we show that the BlsE-catalyzed reaction is initiated by the 5′-deoxyadenosyl (dAdo) radical-mediated hydrogen abstraction from a sugar carbon of the substrate cytosylglucuronic acid (CGA), and does not involve a carboxyl radical as has been proposed for 4-hydroxyphenylacetate decarboxylase (HPAD). Our study reveals that BlsE represents a mechanistically new type of radical-based decarboxylase.
Stereochemistry of C-3 deoxygenation of sugar nucleosides: Formation of pentopyranine C from [3-2H]-D-glucose by Streptomyces griseochromogenes
Gould, Steven J.,Guo, Jincan
, p. 10176 - 10181 (2007/10/02)
Cytosylglucuronic acid (CGA) has previously been shown to be the first intermediate in the biosynthesis of the antibiotic blasticidin S (BS), produced by Streptomyces griseochromogenes. Addition of aminooxyacetic acid (AOAA), an inhibitor of pyridoxal phosphate/pyridoxamine phosphate-dependent transaminases, to 5. griseochromogenes fermentations led to substantial accumulations of CGA and pentopyranine C (PPNC, a shunt metabolite which has undergone decarboxylation at C-5′, deoxygenation at C-3′, and epimerization at C-4′) and to substantial reductions in the production of BS and N-demethylBS. In contrast, inhibitors of glutamine-dependent amidotransferases had little effect. [3-2H]-D-Glucose was fed to a fermentation of S. griseochromogenes containing arginine hydroxamate, an inhibitor of arginine biosynthesis, and a large quantity of cytosine-currently the best conditions for maximum production of CGA and PPNC. This yielded cytosyl[3′-2H]glucuronic acid, an 85:15 mixture of [3′-2Haxial]- and [3′-2Hequatorial]PPNC, and a small amount of a 46:54 mixture of [3′-2Haxial]- and [3′-2Hequatorial]pentopyranone (the immediate precursor to PPNC). The relationship of this C-3 sugar deoxygenation to blasticidin S biosynthesis and to the pyridoxamine phosphate-dependent CDP-4-keto-6-deoxy-D-glucose-3-dehydrase reaction which is central to cell-wall lipopolysaccharide biosynthesis of Gram-negative bacteria is discussed.
