title: Structure and activity of human mitochondrial peptide deformylase, a novel cancer target.
abstract: Peptide deformylase proteins (PDFs) participate in the N-terminal methionine excision pathway of newly synthesized peptides. We show that the human PDF (HsPDF) can deformylate its putative substrates derived from mitochondrial DNA-encoded proteins. The first structural model of a mammalian PDF (1.7 A), HsPDF, shows a dimer with conserved topology of the catalytic residues and fold as non-mammalian PDFs. The HsPDF C-terminus topology and the presence of a helical loop (H2 and H3), however, shape a characteristic active site entrance. The structure of HsPDF bound to the peptidomimetic inhibitor actinonin (1.7 A) identified the substrate-binding site. A defined S1' pocket, but no S2' or S3' substrate-binding pockets, exists. A conservation of PDF-actinonin interaction across PDFs was observed. Despite the lack of true S2' and S3' binding pockets, confirmed through peptide binding modeling, enzyme kinetics suggest a combined contribution from P2'and P3' positions of a formylated peptide substrate to turnover.
authors.affiliation: Molecular Pharmacology and Chemistry Program, Sloan-Kettering Institute, 415 E. 68th Street Zuckerman Z1941, New York, NY 10065, USA.
authors.forename: Sindy
authors.initials: S
authors.lastname: Escobar-Alvarez
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Goldgur
authors.forename: Guangli
authors.initials: G
authors.lastname: Yang
authors.forename: Ouathek
authors.initials: O
authors.lastname: Ouerfelli
authors.forename: Yueming
authors.initials: Y
authors.lastname: Li
authors.forename: David A
authors.initials: DA
authors.lastname: Scheinberg
mesh_terms: D000581:Amidohydrolases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001483:Base Sequence; D020134:Catalytic Domain; D017124:Conserved Sequence; D018360:Crystallography, X-Ray; D017931:DNA Primers / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics; D019281:Dimerization; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D008928:Mitochondria / Q000201:enzymology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009369:Neoplasms / Q000188:drug therapy / Q000201:enzymology; D009842:Oligopeptides / Q000737:chemistry / Q000235:genetics; D017510:Protein Folding; D020836:Protein Structure, Quaternary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D055672:Static Electricity; D013379:Substrate Specificity
chemical_list: D017931:DNA Primers; D004272:DNA, Mitochondrial; D009842:Oligopeptides; D011994:Recombinant Proteins; D000581:Amidohydrolases; C084507:peptide deformylase