Recombinant protein and fragments thereof, method for producing said recombinant protein, synthetic gene and use of the recombinant protein

[0073] Here, a novel class of thrombin inhibitors, in particular direct and specific thrombin inhibitors modified from sculptin identified in transcriptome analysis of tick salivary glands, will be described. It consists of 168 residues with four identical repeats and exhibits evolutionary divergence from classical hirudins. The recombinant protein is a competitive, specific and reversible thrombin inhibitor with a K of 18.5±2.2pM. It is slowly digested by thrombin and loses its inhibitory activity. Thus, the recombinant protein is hydrolyzed by Factor Xa, and each polypeptide fragment is capable of inhibiting thrombin in an independent manner. A single domain of the recombinant protein, which retains only about 45% of its inhibitory activity, has been proposed to bind thrombin in a bivalent fashion. Forming a helix / small turn-like structure by incorporating residues from the active site of the recombinant protein domain would make it the most potent thrombin inhibitor compar