title: Peptidase inhibitors from the salivary glands of the cockroach Nauphoeta cinerea.
abstract: Inhibitory activity against subtilisin, proteinase K, chymotrypsin and trypsin was detected in the salivary glands and saliva of the cockroach Nauphoeta cinerea (Blattoptera: Blaberidae). Fractionation of the salivary glands extract by affinity chromatography followed by reverse-phase HPLC yielded five subtilisin-inhibiting peptides with molecular masses ranging from 5 to 14 kDa. N-terminal sequences and subsequently full-length cDNAs of inhibitors designated NcPIa and NcPIb were obtained. The NcPIa cDNA contains 216 nucleotides and encodes a pre-peptide of 72 amino-acid residues of which 19 make up the signal peptide. The cDNA of NcPIb consists of 240 nucleotides and yields a putative secretory peptide of 80 amino-acid residues. Mature NcPIa (5906.6 Da, 53 residues) and NcPIb (6713.3 Da, 60 residues) are structurally similar (65.4% amino acid overlap) single-domain Kazal-type peptidase inhibitors. NcPIa with Arg in P1 position and typical Kazal motif VCGSD interacted stoichiometrically (1:1) with subtilisin and was slightly less active against proteinase K. NcPIb with Leu in P1 and modified Kazal motif ICGSD had similar activity on subtilisin and no on proteinase K but was active on chymotrypsin.
authors.affiliation: Biology Centre ASCR, Institute of Entomology, Branisovská 31, 370 05 Ceské Budejovice, Czech Republic. taranushenko@entu.cas.cz
authors.forename: Yuliya
authors.initials: Y
authors.lastname: Taranushenko
authors.forename: Konstantin S
authors.initials: KS
authors.lastname: Vinokurov
authors.forename: Barbara
authors.initials: B
authors.lastname: Kludkiewicz
authors.forename: Dalibor
authors.initials: D
authors.lastname: Kodrík
authors.forename: Frantisek
authors.initials: F
authors.lastname: Sehnal
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003058:Cockroaches / Q000378:metabolism*; D005786:Gene Expression Regulation; D008969:Molecular Sequence Data; D010447:Peptide Hydrolases / Q000378:metabolism*; D011480:Protease Inhibitors / Q000378:metabolism*
chemical_list: D011480:Protease Inhibitors; D010447:Peptide Hydrolases