The cleavage of β‐chain in bovine fibrinogen DH fragment (95 kDa) leads to a significant increase in its anticlotting activity

[摘要]

It is shown that in the presence of Ca²⁺ plasmin converts bovine fibrinogen fragment D_H (95 kDa) into D_LA fragment by the cleavage of its β-chain Arg₃₇₂Thr₃₇₃ bond. D_LA fragment consists of two components (82 and 12 kDa) held together by non-covalent bonds and has 3.5-fold higher anticlotting activity than D_H fragment. The D_H to D_LA fragment conversion leads to the destabilization of thermolabile domains of the latter without the loss of their compact structure. The results obtained show that the activation of D_H fragment by the cleavage of its Arg₃₇₂Thr₃₇₃ bond bears some resemblance to the general activation of proenzyme into enzyme.

[学科分类] 生物化学/生物物理

[关键词] Fragment DH;Anticlotting activity;Proteolysis;Activation;Sequence homology