Characterization of a Citrulline 4-Hydroxylase from Nonribosomal Peptide GE81112 Biosynthesis and Engineering of Its Substrate Specificity for the Chemoenzymatic Synthesis of Enduracididine.

ABSTRACT: The GE81112 tetrapeptides are a small family of unusual nonribosomal peptide congeners with potent inhibitory activity against prokaryotic translation initiation. With the exception of the 3-hydroxy-l-pipecolic acid unit, little is known about the biosynthetic origins of the non-proteinogenic amino acid monomers of the natural product family. Here, we elucidate the biogenesis of the 4-hydroxy-l-citrulline unit and establish the role of an iron- and ?-ketoglutarate-dependent enzyme (Fe/?KG) in the pathway. Homology modelling and sequence alignment analysis further facilitate the rational engineering of this enzyme to become a specific 4-arginine hydroxylase. We subsequently demonstrate the utility of this engineered enzyme in the synthesis of a dipeptide fragment of the antibiotic enduracidin. This work highlights the value of applying a bioinformatics-guided approach in the discovery of novel enzymes and engineering of new catalytic activity into existing ones.

SUBMITTER: Zwick CR 

PROVIDER: S-EPMC6917913 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature