Isolation and Identification of Proteins with Anti-tumor and Fibrinolysogen Kinase Activities from Eisenia foetida

ZHAO Rui, JI Jian-Guo, TONG Yuan-Peng, CHEN Qian, PU Hai, RU Bing-Gen*

£¨ Proteomics Research Group£¬ School of Life Science, Peking University£¬

Beijing 100871, China £©

Abstract    Proteins from Eisenia foetida possess many biological activities. A group of proteins precipitated by ethanol were isolated and purified by Sephadex G-75 and HiPrep 16/60 DEAE columns, then identified by one- or two- dimensional electrophoresis and mass spectrometry. 2D gel experiments displayed that the pI of proteins from Eisenia foetidaª«were mainly from 3.0 to 4.0. Anti-tumor and kinase activities were determined by in vitro experiments. The enthanol fraction D2(8) showed both of the activities. These ethanol-precipitated proteins were identified further by native polyacrylamide electrophoresis, the protein spots were cut off from gels and digested by trypsin, the peptide mass fingerprints (PMFs) were determined by mass spectrometry. PMF, molecular weight, amino acid composition and N-terminus of 6 proteins were characterized, and band 9 was identified as D2(8). The results suggested that there exist proteins in Eisenia foetida possessed both anti-tumor and fibrinolysogen kinase activities. These methods can be used for identification of the natural bioactive proteins.
Key words Eisenia Foetida; aiti-tumor; kinase; protein

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