Cloning and Expression of a Novel Protease with Fibrinolytic Activity from Arenicola cristata

cDNA of a novel protease, designated as AFEI, was cloned from digestive tract of Arenicola cristata by RACE. The cDNA of AFEIcomprised 897bp and an open reading frame that encoded polypeptides of 264 amino acid residues. AFEIshowed similarity to serine protease family and contained the conserved catalytic amino acid residues. The gene encoding the active form of AFEIwas expressed in E.coli and the purified recombinant protein could dissolve an artificial fibrin plate with plasminogen, which indicated the recombinant protein might be a plasminogen activator for thrombosis therapy.

Anti-Tumor Effects of a Newly Cloned Serine Protease from the Marine Annelid, Arenicola cristata

We cloned a new serine protease gene from the marine annelid,Arenicola cristataby rapid amplification of cDNA ends. The full-length cDNA of 901bp contained an open reading frame of 774bp encoding 258 amino acids. Sequence analysis of the deduced amino acids indicated that this protease belonged to serine protease family and contained highly conserved sequence GDSGGP. An expression vector, harboring the mature peptide ofArenicola cristataprotease, was constructed and transformed intoE.coli. The purified recombinant protein could inhibit proliferation of cancer cells in a dose-dependant way and induce apoptosis. These results indicated that the recombinant protease ofArenicola cristata, as a new member of serine protease family, might be valuable in developing anti-tumor agents.

Cloning and Activity Analysis of a New Protease from Arenicola cristata

The protease gene Arenicola cristata was cloned, sequenced, and expressed in E.coli and the activity of the recombinant protein was investigated. The full-length cDNA of 880 bp consisted of an ORF of 813bp encoding 270 amino acids. This protease contained highly conserved GDSGGP sequence and revealed high homology with trypsin-like proteases of serine family. The recombinant protein for the active form of the protease was purified by affinity chromatography. The activity analysis of the recombinant protein suggested that it was probably a plasminogen activator.