title: The effect of cleavage by a Crotalus atrox alpha-proteinase fraction on the properties of C1-inhibitor.
abstract: The effect of cleavage of C1-inhibitor at Pro36 by a Crotalus atrox alpha-proteinase fraction on the properties of this serpin was studied. This truncated C1-inhibitor (des 1-36) was fully active as an inhibitor of kallikrein, beta-factor XIIa, and C1s, and modulated the functions of C1 in a normal manner. Also, the half-life of the truncated protein in the circulation of rabbits, both alone and in complex with C1, was not altered. These results show that shock-like symptoms caused by C. atrox envenomation are not attributable to a deficiency in C1-inhibitor caused by the action of the metalloproteinase in the alpha-proteinase fraction.
authors.affiliation: Department of Medicine, Vanderbilt University, Nashville, TN 37232, USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Patston
authors.forename: M
authors.initials: M
authors.lastname: Qi
authors.forename: J A
authors.initials: JA
authors.lastname: Schifferli
authors.forename: M
authors.initials: M
authors.lastname: Schapira
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003174:Complement C1 Inactivator Proteins / Q000378:metabolism*; D003435:Crotalid Venoms / Q000032:analysis / Q000633:toxicity*; D017839:Crotalus; D006801:Humans; D007610:Kallikreins / Q000378:metabolism; D008666:Metalloendopeptidases / Q000494:pharmacology*; D008969:Molecular Sequence Data; D011817:Rabbits
chemical_list: D003174:Complement C1 Inactivator Proteins; D003435:Crotalid Venoms; D007610:Kallikreins; D008666:Metalloendopeptidases