[Isolation, purification and properties of a carboxypeptidase inhibitor from human blood serum].
Partially purified low molecular component, which inhibited the carboxypeptidase N activity in samples with hippuryl-L-lysine and bradikinine as substrates, was isolated from human blood serum by means of chromatography on DEAE-Sephadex, ultrafiltration of the fractions obtained through Amicon membranes UM-10 or UM-2 and subsequent gel filtration through Sephadex G-10. The probable molecular weight of the inhibitor was 2000. The inhibitor was thermolabile; its inhibitory activity was decreased by 50% after 30 min boiling in 0.01 M phosphate buffer, pH 7.8. Trypsin and chymotrypsin did not influence the inhibitory properties of the factor. Hydrolysis of the low molecular component in 6 N HCl at 110 degrees C within 18 hrs and subsequent studies of the amino acid composition showed a number of amino acids in the hydrolysate; the hydrolysate exhibited the inhibitor activity of the initial substance.
D000596:Amino Acids / Q000032:analysis; D002268:Carboxypeptidases / Q000037:antagonists & inhibitors*; D002918:Chymotrypsin; D004355:Drug Stability; D006358:Hot Temperature; D006801:Humans; D008970:Molecular Weight; D009842:Oligopeptides / Q000032:analysis / Q000097:blood* / Q000494:pharmacology; D014357:Trypsin; D014462:Ultrafiltration
D000596:Amino Acids; D009842:Oligopeptides; D002268:Carboxypeptidases; D002918:Chymotrypsin; D014357:Trypsin
Vydelenie, ochistka i svoĭstva ingibitora karboksipeptidazy i iz syvorotki krovi cheloveka