【Abstract】 The studies of SCAIF I(an unknown protein) by HPLC and ESIMS was reported in this paper. The SCAIF I is a kind of antiangiogenesis extracted from shark cartilage. The extracted protein was purified by HPLC and then studied by ESIMS. The molecule weight of the SCAIF I protein was confirmed to be 15 601 in the first time. Peptide map of the unknown protein was obtained by HPLC ESIMS with a trypsin digestion and possible partial sequences were deduced with the online CID technique. With partial sequence information the homologous proteins are searched with protein database. The homology of SCAIF I summarized in this work is useful in further studies of this unknown protein.更多还原