Penicillin V acylase (PVA), also known as conjugated bile salt acid hydrolase (CBAH), catalyzes the hydrolysis of penicillin V to yield 6-amino penicillanic acid (6-APA), an important key intermediate of semisynthetic penicillins. PVA has an N-terminal nucleophilic cysteine, as do other members of the Ntn hydrolase family to which PVA belongs. This nucleophilic cysteine is exposed by post-translational prossessing of the PVA precursor. PVA forms a homotetramer.
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