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Updated: Feb 13, 2026

Peptide-based Identification of Functional Motifs and their Binding Partners
Published on: June 30, 2013
Characterization of Leader Peptide Binding During Catalysis by the Nisin Dehydratase NisB
Lindsay M Repka1, Kenton J Hetrick1, See Hyun Chee1
1Department of Chemistry and Howard Hughes Medical Institute, University of Illinois, Urbana-Champaign , 600 South Mathews Avenue , Urbana , Illinois 61801 , United States.
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.
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