Prolyl 4-Hydroxylase: Substrate Isosteres in Which an (E)- or (Z)-Alkene Replaces the Prolyl Peptide Bond.

Biochemistry
Authors
Abstract

Collagen prolyl 4-hydroxylases (CP4Hs) catalyze a prevalent posttranslational modification, the hydroxylation of (2S)-proline residues in protocollagen strands. The ensuing (2S,4R)-4-hydroxyproline residues are necessary for the conformational stability of the collagen triple helix. Prolyl peptide bonds isomerize between cis and trans isomers, and the preference of the enzyme is unknown. We synthesized alkene isosteres of the cis and trans isomers to probe the conformational preferences of human CP4H1. We discovered that the presence of a prolyl peptide bond is necessary for catalysis. The cis isostere is, however, an inhibitor with a potency greater than that of the trans isostere, suggesting that the cis conformation of a prolyl peptide bond is recognized preferentially. Comparative studies with a Chlamydomonas reinhardtii P4H, which has a similar catalytic domain but lacks an N-terminal substrate-binding domain, showed a similar preference for the cis isostere. These findings support the hypothesis that the catalytic domain of CP4Hs recognizes the cis conformation of the prolyl peptide bond and inform the use of alkenes as isosteres for peptide bonds.

Year of Publication
2017
Journal
Biochemistry
Volume
56
Issue
1
Pages
219-227
Date Published
2017 Jan 10
ISSN
1520-4995
DOI
10.1021/acs.biochem.6b00976
PubMed ID
28001367
PubMed Central ID
PMC5225157
Links
Grant list
F32 GM098032 / GM / NIGMS NIH HHS / United States
T32 GM007215 / GM / NIGMS NIH HHS / United States
P41 GM103399 / GM / NIGMS NIH HHS / United States
R01 AR044276 / AR / NIAMS NIH HHS / United States
F32 GM096712 / GM / NIGMS NIH HHS / United States