title: Structural aspects of human kininogens.
abstract: Kininogens have been purified from human plasma to apparent homogeneity. Native human LMW kininogen is a single-chain (glyco-) protein of molecular weight 68,000, which is converted to a two-chain protein by limited proteolysis with tissue kallikrein to form a heavy chain (Mr 62,000) and a light chain (Mr 4,000). Human HMW kininogen represents a single chain (glyco-)protein of Mr 114,000 which is split into two chains of similar size (H-chain of Mr 58,000 and L-chain of Mr 62,000) by limited proteolysis with tissue kallikrein. Sequence analysis of the isolated L-chain of human MW kininogen indicates a partial homology to the corresponding fragment-1.2 of bovine HMW kininogen. Purified kininogens readily form self-aggregates ranging from dimer to hexamer (HMW kininogen) and from dimer to decamer (LMW kininogen), respectively. Self-association is completely reversible in the presence of dissociating agents. Preliminary evidence suggests that oligomerisation is mediated by the H-chain common to the two types of kininogens.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D055598:Chemical Phenomena; D002621:Chemistry; D006801:Humans; D007610:Kallikreins / Q000494:pharmacology; D007704:Kininogens / Q000302:isolation & purification / Q000378:metabolism; D007705:Kinins / Q000378:metabolism; D046911:Macromolecular Substances; D008970:Molecular Weight
chemical_list: D007704:Kininogens; D007705:Kinins; D046911:Macromolecular Substances; D007610:Kallikreins