title: Prolyl 4-Hydroxylase: Substrate Isosteres in Which an (E)- or (Z)-Alkene Replaces the Prolyl Peptide Bond.
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.
authors.affiliation: Department of Biochemistry, ‡Graduate Program in Biophysics, and §Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States.
authors.forename: James D
authors.initials: JD
authors.lastname: Vasta
authors.affiliation: Department of Biochemistry, ‡Graduate Program in Biophysics, and §Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States.
authors.forename: Amit
authors.initials: A
authors.lastname: Choudhary
authors.affiliation: Department of Biochemistry, ‡Graduate Program in Biophysics, and §Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States.
authors.forename: Katrina H
authors.initials: KH
authors.lastname: Jensen
authors.affiliation: Department of Biochemistry, ‡Graduate Program in Biophysics, and §Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States.
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: McGrath
authors.affiliation: Department of Biochemistry, ‡Graduate Program in Biophysics, and §Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States.
authors.forename: Ronald T
authors.identifier: http://orcid.org/0000-0001-7164-1719
authors.initials: RT
authors.lastname: Raines
mesh_terms: D000475:Alkenes / Q000737:chemistry* / Q000378:metabolism; D020134:Catalytic Domain; D016825:Chlamydomonas reinhardtii / Q000201:enzymology; D006801:Humans; D006900:Hydroxylation; D006909:Hydroxyproline / Q000737:chemistry* / Q000378:metabolism; D007536:Isomerism; D007700:Kinetics; D008956:Models, Chemical; D015394:Molecular Structure; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism; D011393:Procollagen-Proline Dioxygenase / Q000737:chemistry* / Q000378:metabolism; D011392:Proline / Q000737:chemistry* / Q000378:metabolism; D064828:Prolyl Hydroxylases / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding; D013045:Species Specificity; D013379:Substrate Specificity
chemical_list: D000475:Alkenes; D010455:Peptides; D011392:Proline; D064828:Prolyl Hydroxylases; D011393:Procollagen-Proline Dioxygenase; D006909:Hydroxyproline