title: The X-ray crystal structure of pyrrolidone-carboxylate peptidase from hyperthermophilic archaea Pyrococcus horikoshii.
abstract: The crystal structure of pyrrolidone-carboxylate peptidase (PCP) from hyperthermophilic archaea Pyrococcus horikoshii (PhoPCP) has been determined at 1.6-A resolution by X-ray crystallography. PCP belongs to the C15 family of cysteine protease, and specifically removes the amino terminal pyroglutamate residue from a wide range of N-terminal-blocking peptides. The crystal structure is very similar to that of other hyperthermophiles, Pyrococcus furiosus and Thermococcus litoralis, and even that from the mesophile, Bacillus amyloliquefaciens. The inter-subunit disulfide bonds, which have been proposed as one of the thermostabilizing factors of the PCP from such hyperthermophiles, was not present in PhoPCP. The result suggests that the thermostability of PhoPCP may be obtained by the accumulation of many weak factors.
authors.affiliation: Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Sokabe
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawamura
authors.forename: Naoki
authors.initials: N
authors.lastname: Sakai
authors.forename: Min
authors.initials: M
authors.lastname: Yao
authors.forename: Nobuhisa
authors.initials: N
authors.lastname: Watanabe
authors.forename: Isao
authors.initials: I
authors.lastname: Tanaka
mesh_terms: D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000737:chemistry*; D001407:Bacillus / Q000201:enzymology; D001426:Bacterial Proteins / Q000737:chemistry; D018360:Crystallography, X-Ray; D003546:Cysteine Endopeptidases / Q000737:chemistry; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D019711:Pyrococcus / Q000201:enzymology*; D020027:Pyrococcus furiosus / Q000201:enzymology; D011751:Pyroglutamyl-Peptidase I / Q000737:chemistry*; D011993:Recombinant Fusion Proteins / Q000737:chemistry; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D019712:Thermococcus / Q000201:enzymology
chemical_list: D019843:Archaeal Proteins; D001426:Bacterial Proteins; D011993:Recombinant Fusion Proteins; D011751:Pyroglutamyl-Peptidase I; D003546:Cysteine Endopeptidases