Structural features and anticoagulant activities of a novel natural low molecular weight heparin from the shrimp Penaeus brasiliensis

A natural low molecular weight heparin (8.5 kDa), with an anticoagulant act ivity of 95 IU/mg by the USP assay, was isolated from the shrimp Penaeus br asiliensis. The crustacean heparin was susceptible to both heparinase and h eparitinase II from Flavobacterium heparinum forming tri- and di-sulfated d isaccharides as the mammalian heparins. C-13 and H-1 NMR spectroscopy revea led that the shrimp heparin was enriched in both glucuronic and non-sulfate d iduronic acid residues. The in vitro anticlotting activities in different steps of the coagulation cascade have shown that its anticoagulant action is mainly exerted through the inhibition of factor Xa and heparin cofactor II-mediated inhibition of thrombin. The shrimp heparin has also a potent in vivo antithrombotic activity comparable to the mammalian low molecular wei ght heparins. (C) 1999 Elsevier Science B.V. All rights reserved.