Isolation and purification of the ovulation-inducing factor from seminal plasma in the bactrian camel (Camelus bactrianus)

The purpose of this study was to extract, identify and partially characterize a newly found ovulation-inducing factor, and thus gain our understanding of induced ovulation in biology. In our preliminary research, an ovulation-inducing factor (OIF) was isolated and purified from seminal plasma of the bactrian camel by ion-exchange chromatography on DEAE-cellulose, HPLC and reverse-phase HPLC. The OIF is a peptide with 74 residues and GnRH-iike bioactivity, which is heat-stable in camel seminal plasma because the OIF is wrapped up in several protein layers with different properties. However, purified OIF is degraded when it is exposed to Oxygen or is heated in water. According to the analysis of amino acid components and partial amino acid sequence aminated N-terminus, and its molecular weight, the OIF is completely different from the native-LHRH, LH, HCG, PMSG and PGF-2 alpha. The OIF is a novel ovulation hormone in the bactrian camel, but is similar to that reported in the bull. (C) 2001 by Elsevier Science Inc.