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Characterization of Leader Peptide Binding During Catalysis by the Nisin Dehydratase NisB.

ABSTRACT: The dehydratase NisB performs stepwise tRNAGlu-dependent glutamylation of Ser/Thr residues and subsequent glutamate elimination to effect eight dehydrations in the biosynthesis of the antibacterial peptide nisin. Its substrate, NisA, bears a C-terminal core peptide that is modified and an N-terminal leader peptide (LP) that is not modified but that is required for efficient dehydration. To elucidate the mechanism of LP-NisB interactions during dehydration, we engineered a disulfide that covalently links the NisA LP to NisB. The enzyme fully dehydrated tethered NisA, confirming the functional LP binding site and supporting a mechanism where NisB uses a single LP binding site for glutamylation and elimination. We also show an order of NisA and tRNAGlu binding to NisB that enables dehydration.

SUBMITTER: Repka LM

PROVIDER: S-EPMC5901694 | biostudies-other | 2018 Mar

REPOSITORIES: biostudies-other

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Characterization of Leader Peptide Binding During Catalysis by the Nisin Dehydratase NisB.

Repka Lindsay M LM Hetrick Kenton J KJ Chee See Hyun SH van der Donk Wilfred A WA

Journal of the American Chemical Society 20180320 12

The dehydratase NisB performs stepwise tRNA<sup>Glu</sup>-dependent glutamylation of Ser/Thr residues and subsequent glutamate elimination to effect eight dehydrations in the biosynthesis of the antibacterial peptide nisin. Its substrate, NisA, bears a C-terminal core peptide that is modified and an N-terminal leader peptide (LP) that is not modified but that is required for efficient dehydration. To elucidate the mechanism of LP-NisB interactions during dehydration, we engineered a disulfide th ...[more]

PMID: 29537838

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