A novel fibrinolytic serine protease from the polychaete Nereis (Neanthes) virens (Sars): Purification and characterization

作者：Zhang Yunlong; Cui Jiayue; Zhang Rui; Wang Yanpin; Hong Min^*

来源：Biochimie, 2007, 89(1): 93-103.

DOI：10.1016/j.biochi.2006.07.023

• clamworm
• fibrinolytic activity
• fibrinogenolytic activity
• Nereis virens
• serine protease

A novel fibrinolytic serine protease has been identified and purified to homogeneity from the coelomic fluid of polychaete Nereis (Neanthes) virens (Sars), and named N-V protease. N-V protease is a 29 kDa single chain protein with an isoelectric point of pH 4.5. It hydrolyzes A alpha-chain of fibrinogen with a high efficiency, and the B beta- and gamma-chains (A alpha > B beta > gamma) with a lower efficiency. The proteolytic activity peaks at pH 7.8 is 45 degrees C. The activity is completely inhibited by serine protease inhibitors DFP (I-50 = 5.8 x 10(-4) M) and PMSF (I-50 = 5.5 x 10(-2) M), and almost completely by TLCK (I-50 = 7.7 x 10(-1) M). But aprotinin, elastinal, SBTI, benzamidine, PCMB, EDTA, EGTA, iodoacetate, E64, and beta-mercaptoethanol have no effect on the protease activity. Therefore, N-V protease is identified as a serine protease. The primary amino acid sequence of N-V protease was determined by mass spectrometry (N-V protease, No. P83433). According to the MALDI-TOF MS analysis, there is no existing protein in the NCBI Non-redundant Protein Sequence Database that matches the N-V protease sequence. Therefore, N-V protease is a novel and special protein in N. virens. Furthermore, we have successfully established an expression cDNA library from the whole body of N. virens (data not shown).

• 出版日期2007-1
• 单位吉林大学