Substrate specificity of benzamide synthetase involved in 4-hydroxy-3-nitrosobenzamide biosynthesis

作者：Noguchi Akio; Horinouchi Sueharu; Ohnishi Yasuo^*

来源：Journal of Antibiotics, 2011, 64(1): 93-96.

DOI：10.1038/ja.2010.144

• benzamide synthetase
• glutamine-dependent amidotransferase
• 4-hydroxy-3-nitrosobenzamide
• secondary metabolism
• Streptomyces
• substrate specificity

Glutamine-dependent amidotransferase (Gn-AT) catalyzes the transfer of the amido nitrogen of glutamine to an acceptor substrate to produce glutamate and an aminated product. Although most Gn-ATs are involved in biosyntheses of primary metabolites, some are important in the synthesis of secondary metabolites. Recently, a Gn-AT (NspN) was discovered in the biosynthetic pathway of 4-hydroxy-3-nitorosobenzamide in Streptomyces murayamaensis. NspN converts 3-amino-4-hydroxybenzoic acid (3,4-AHBA) to 3-amino-4-hydroxybenzamide. Here, we report the amino-acceptor substrate specificity of NspN. NspN could use several benzoic acid derivatives as amino-acceptor substrates to produce corresponding benzamides and catalyze the amidation of several carboxylate-type phenylpropanoids, such as p-coumaric acid, cinnamic acid and caffeic acid. NspN showed the highest activity toward its natural substrate 3,4-AHBA among the substrates examined. NspN and related bacterial Gn-ATs may be useful in developing combinatorial biosynthetic strategies for benzamide derivatives, which could, in turn, be used as therapeutic agents for a variety of diseases. The Journal of Antibiotics (2011) 64, 93-96; doi:10.1038/ja.2010.144; published online 17 November 2010

• 出版日期2011-1