摘要
The clotting protein(CP) plays important and diverse roles in crustaceans,such as coagulation and lipid transportation.A clotting protein was purified from the hemolymph of Chinese shrimp Fenneropenaeus chinensis(named as Fc-CP) with Q sepharose HP anion-exchange chromatography and phenyl sepharose HP hydrophobic interaction chromatography.Fc-CP was able to form stable clots in vitro in the presence of hemocyte lysate and Ca2+,suggesting that the clotting reaction is catalyzed by a Ca2+-dependent transglutaminase in shrimp hemocytes.The molecular mass of Fc-CP was 380 kDa under non-reducing conditions and 190 kDa under reducing conditions as was determined with SDS-PAGE.CP exists as disulfide-linked homodimers and oligomers.The N-terminal amino acid sequence of Fc-CP was identical to that of shrimps including Penaeus monodon,Farfantepenaeus paulensis and Litopenaeus vannamei;and similar to that of other decapods.The purified Fc-CP was digested with trypsin and verified on an ABI 4700 matrix-assisted laser desorption/ionization tandem time-of-flight(MALDI-TOF/TOF) mass spectrometry.Our results will aid to better understanding the coagulation mechanism of shrimp hemolymph.
The clotting protein （CP） plays important and diverse roles in crustaceans, such as coagulation and lipid transportation. A clotting protein was purified from the hemolymph of Chinese shrimp Fenneropenaeus chinensis （named as Fc-CP） with Q sepha- rose HP anion-exchange chromatography and phenyl sepharose HP hydrophobic interaction chromatography. Fc-CP was able to form stable clots in vitro in the presence of hemocyte lysate and Ca2~, suggesting that the clotting reaction is catalyzed by a Ca2＋-dependent transglutaminase in shrimp hemocytes. The molecular mass of Fc-CP was 380 kDa under non-reducing conditions and 190 kDa under reducing conditions as was determined with SDS-PAGE. CP exists as disulfide-linked homodimers and oligomers The N-terminal amino acid sequence of Fc-CP was identical to that of shrimps including Penaeus monodon, Farfantepenaeus paulensis and Litopenaeus vannamei; and similar to that of other decapods. The purified Fc-CP was digested with trypsin and veri- fied on an ABI 4700 matrix-assisted laser desorption/ionization tandem time-of-flight （MALDI-TOF/TOF） mass spectrometry. Our results will aid to better understanding the coagulation mechanism of shrimp hemolymph.
基金
supported by the National Natural Science Foundation of China(No.30600458)
