title: Expression, purification and functional characterisation of a Kunitz-type module from chicken type VI collagen.
abstract: The primary amino acid sequence of the carboxyl-terminal portion of the alpha 3 chain of chicken type VI collagen (K-VI) presents a 58-residue motif with a high degree of homology with members of the Kunitz serine-proteinase inhibitors family. This module was cloned, expressed in E. coli, purified and compared to the bovine pancreatic trypsin inhibitor (BPTI) in an inhibition profile assay of two serine proteases, trypsin and plasmin. We found that recombinant K-VI is not endowed with inhibitory activity but it slightly activates both plasmin and trypsin, differently from other members of the family. Moreover, the ability to inhibit the serine protease activity is also lacking in the intact type VI collagen molecule.
mesh_terms: D000818:Animals; D007611:Aprotinin / Q000737:chemistry* / Q000494:pharmacology; D001483:Base Sequence; D002417:Cattle; D002645:Chickens; D003001:Cloning, Molecular; D003094:Collagen / Q000096:biosynthesis* / Q000737:chemistry* / Q000494:pharmacology; D004926:Escherichia coli; D005341:Fibrinolysin / Q000037:antagonists & inhibitors; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000494:pharmacology*; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000494:pharmacology; D014357:Trypsin / Q000378:metabolism; D001616:beta-Galactosidase / Q000096:biosynthesis
chemical_list: D010446:Peptide Fragments; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; D003094:Collagen; D007611:Aprotinin; D001616:beta-Galactosidase; D014357:Trypsin; D005341:Fibrinolysin