enzyme is part of the chloroeremomycin biosynthetic cluster. Non-heme iron dioxygenase HmaS catalyzes the synthesis of L-4-hydroxymandelate from 4-hydroxyphenylpyruvate. The L-4-hydroxymandelate is subsequently converted to L-4-hydroxyphenylglycine via L-4-hydroxymandelate oxidase Hmo catalyzed conversion of L-4-hydroxymandelate to L-4-hydroxybenzoylformate followed by 4-hydroxyphenylglycine transaminase HpgT catalyzed transamination of 4-hydroxybenzoylformate to 4-hydroxyphenylglycine. The biosynthesis of L-4-hydroxyphenylglycine is proposed to be a catalytic cycle initiated by the production of 4-hydroxyphenylpyruvate
engineering of Escherichia coli for biosynthesis of L-phenylglycine from glucose. The enzymes HmaS (L-4-hydroxymandelate synthase), Hmo (L-4-hydroxymandelate oxidase) and HpgT (L-4-hydroxyphenylglycine transaminase) are heterologously expressed in Escherichia coli. HpgT conversing phenylglyoxylate to L-phenylglycine uses an unusual aminodonor L-phenylalanine, which releases another phenylpyruvate as the substrate of HmaS. A recycle-reaction maximizes the utilization of precursor phenylpyruvate. After deletionof tyrB and aspC, L-phenylglycine yield increases by 12.6fold. The L-phenylglycine yield is further improved by 14.9fold after enhancing hmaS expression
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2.6.1.B17 4-hydroxyphenylglycine transaminase
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