A novel extracellular protease with fibrinolytic activity from the culture supernatant of Cordyceps sinensis: purification and characterization.
A novel serine protease with fibrinolytic activity named CSP was purified from the culture supernatant of the fungus Cordyceps sinensis, a kind of Chinese herbal medicine. Analysis of the purified enzyme by SDS-PAGE indicated that CSP was a single polypeptide chain with an apparent molecular weight of 31 kDa, and N-terminal sequencing revealed that the first ten amino acid residues of the enzyme were Ala-Leu-Ala-Thr-Gln-His-Gly-Ala-Pro-Trp-. When casein was used as a substrate, the proteolytic activity of CSP reached its maximum at pH 7.0 and 40 degrees C. The effect of chemical agents on the enzyme activity indicated that CSP is a serine protease with a free cysteine residue near the active site. It hydrolysed fibrinogen, fibrin and casein with a high efficiency, while hydrolysing bovine serum albumin (BSA) and human serum albumin (HSA) to a lesser extent. CSP was found to be a plasmin-like protease, but not a plasminogen activator, and it preferentially cleaved the A alpha chain of fibrinogen and the alpha-chain of fibrin. Therefore, the extracellular protein CSP may represent a potential new therapeutic agent for the treatment of thrombosis.
Li
Hua-ping
HP
State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, Hubei Province, 430072, PR China.
Hu
Zheng
Z
Yuan
Jiang-lan
JL
Fan
Han-dong
HD
Chen
Wei
W
Wang
Shi-jia
SJ
Zheng
Shan-shan
SS
Zheng
Zhong-liang
ZL
Zou
Guo-lin
GL
D000595:Amino Acid Sequence; D032661:Cordyceps / Q000201:enzymology*; D005337:Fibrin / Q000378:metabolism; D005340:Fibrinogen / Q000378:metabolism; D005342:Fibrinolysis / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D012697:Serine Endopeptidases / Q000737:chemistry / Q000302:isolation & purification*; D013379:Substrate Specificity; D013696:Temperature
D005337:Fibrin; D005340:Fibrinogen; D012697:Serine Endopeptidases