Purification and characterization of a plasmin-like protease from Tenodera sinensis (Chinese mantis).
A novel type of protease (mantis egg fibrinolytic enzyme, MEF-2) was isolated from the egg cases of Tenodera sinensis. The protease was homogeneous by SDS-PAGE and its apparent molecular mass was 32,900 Da. The amino acids in the N-terminal region were Ile-Val-Gly-Gly-Glu-Glu-Ala-Val-Ala-Gly-Asp-Phe-Pro-Ile-Val-Ser-Leu-Gln-Glu. The enzyme was inhibited by PMSF, TLCK, aprotinin, benzamidine, soybean trypsin inhibitor and also slightly by elastatinal, EDTA, EGTA, cysteine and beta-mercaptoethanol, but TPCK, iodoacetate and E-64 did not affect the activity. MEF-2 was not sensitive to alpha(1)-antitrypsin but antithrombin III and alpha(2)-antiplasmin inhibited the enzyme. MEF-2 preferentially cleaved the oxidized B-chain of insulin between Arg(22) and Gly(23). Among chromogenic protease substrates, the most susceptible to MEF-2 hydrolysis was benzoyl-Phe-Val-Arg-p-nitroanilide with maximal activity at 30 degrees C and pH 5.0. These results indicate that MEF-2 belongs to the trypsin family. Upon incubation of crosslinked fibrin with MEF-2, a steady increase of D-dimer suggests that the enzyme has a strong fibrinolytic activity. In conclusion, MEF-2 is a new type of proteolytic enzyme and has some potential for practical application in fibrinolysis.
Hahn
B S
BS
Natural Products Research Institute, Seoul National University, 28 Yeonkun-Dong, Jongno-Ku, Seoul 110-460, South Korea.
Cho
S Y
SY
Ahn
M Y
MY
Kim
Y S
YS
D000595:Amino Acid Sequence; D000596:Amino Acids; D002942:Circular Dichroism; D019281:Dimerization; D005341:Fibrinolysin / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D020050:Mantodea / Q000201:enzymology*; D008969:Molecular Sequence Data; D010958:Plasminogen / Q000378:metabolism; D013379:Substrate Specificity
D000596:Amino Acids; D010958:Plasminogen; D005341:Fibrinolysin