title: Characterization of a glutenin-specific serine proteinase of Sunn bug Eurygaster integricepts Put.
abstract: Glutenin hydrolyzing proteinases (GHPs) have been purified, by affinity chromatography, from wheat seeds damaged by the Sunn bug Eurygaster integriceps (Hemiptera, Scutelleridae). A 28 kDa protein was partially sequenced by mass spectrometry and Edman degradation which showed homology to serine proteases from various insects. Three full length clones were obtained from cDNA isolated from Sunn bug salivary glands using degenerate PCR based on the sequences obtained. The cleavage site of the protease was determined using recombinant and synthetic peptides and shown to be between the consensus hexapeptide and nonapeptide repeat motifs present in the high molecular weight subunits of wheat glutenin (PGQGQQ∧GYYPTSLQQ). Homology models were generated for the three proteinases identified in this study using the high resolution X-ray structure of a crayfish (Pontastacus leptodactylus) trypsin complexed with a peptide inhibitor as template (PDB accession 2F91). The novel specificity of this protease may find applications in both fundamental and applied studies.
authors.affiliation: All-Russian Institute for Plant Protection (VIZR), 3 Podbelsky, Pushkin, St. Petersburg 196608, Russia.
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Konarev
authors.forename: Frédéric
authors.initials: F
authors.lastname: Beaudoin
authors.forename: Justin
authors.initials: J
authors.lastname: Marsh
authors.forename: Nina A
authors.initials: NA
authors.lastname: Vilkova
authors.forename: Ludmila I
authors.initials: LI
authors.lastname: Nefedova
authors.forename: Dilek
authors.initials: D
authors.lastname: Sivri
authors.forename: Hamit
authors.initials: H
authors.lastname: Köksel
authors.forename: Peter R
authors.initials: PR
authors.lastname: Shewry
authors.forename: Alison
authors.initials: A
authors.lastname: Lovegrove
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005983:Glutens / Q000737:chemistry / Q000378:metabolism; D020062:Heteroptera / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D019476:Insect Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D012469:Salivary Glands / Q000737:chemistry / Q000201:enzymology; D016415:Sequence Alignment; D057057:Serine Proteases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D019476:Insect Proteins; D005983:Glutens; D057057:Serine Proteases; C037302:glutenin