[Amino acid makeup, structural characteristics and substrate specificity of rabbit plasma kininogen].
Highly purified kininogen preparation with the activity of 16-18 int. units per mg was isolated from rabbit blood serum. Its molecular weight was estimated to be 54 000 by gel filtration through Sephadex G-200. Leucine was identified as N-terminal amino acid by the dansylation method. Rabbit kininogen consists of 394 amino acid residues (except tryptophane). Amino acid composition of kininogen is characterized by a high content of dicarbonic amino acids, proline and by a low content of methionine. Kininogen molecule does not contain SH-groups. 13.1-13.5 SH-groups were found in kininogen after the reduction of S-S bonds with beta-mercaptoethanol in the presence of 8 M urea, thus indicating the presence of 6-7 S-S bonds in kininogen molecule. Kininogen group does not occupy C-terminal position in the molecule, because the treatment of the protein with carboxypeptidase B does not change the content of bradykinine in it. Purified kininogen preparation is a substrate for kallikrein from rabbit blood plasma, human saliva and trypsin. Unlike trypsin, kallikreines from human blood plasma and saliva release kinines from kininogen with reduced S-S bonds. Under spontaneous reoxidation of reduced S-S bonds up to 90%, substate properties of kininogen for tripsin recover only by 50%. Rabbit kininogen is similar to beef kininogen II in its molecular weight, amino acid composition and the number of S-S bonds.
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis*; D000818:Animals; D001322:Autoanalysis; D001665:Binding Sites; D002417:Cattle; D002850:Chromatography, Gel; D002855:Chromatography, Thin Layer; D004586:Electrophoresis; D006801:Humans; D007610:Kallikreins / Q000494:pharmacology; D007704:Kininogens / Q000097:blood* / Q000302:isolation & purification; D008297:Male; D008968:Molecular Conformation; D008970:Molecular Weight; D010084:Oxidation-Reduction; D011817:Rabbits; D013438:Sulfhydryl Compounds / Q000032:analysis
D000596:Amino Acids; D007704:Kininogens; D013438:Sulfhydryl Compounds; D007610:Kallikreins
Aminokislotnyĭ sostav, osobennosti stroeniia i substratnaia spetsifichnost' kininogena plazmy krolika