Purification And Characterization Of The Female Specific Protein In The Marine Prawn, Fenneropenaeus Chinensis

A purified vitellin was isolatied from the mature ovaries of the marine prawn,Fenneropenaeus chinensis with two metods:chromatography(SephadexG-150 and DEAE-Cellulose-32) and a modified method(EDTA-Mg²⁺ precipitation and electroelution),. the vitellins in ova and nauplius larvae (N₄ stage)were purified with electroelution.The vitellin in ovaries was a lipo-glyco-phospho-caroprotein on the basis of experimental results,with an apparent molecular weight of 409 ku.Its pI was 5.4, containing 8.7% oligosaccharides.Five subunits(202 ku,171 ku,105 ku,80 ku å’Œ73 ku) and one disulfide bond were detected. Six subunits(202 ku,188 ku,171 ku,105 ku,80 ku,66 ku)were found in the vitellin of ova,and the apparent molecular of this protein was 404 ku,higher than the vitellin of lavae(390 ku) in which five subunits(202 ku,188 ku,171 ku,105 ku,80 ku)were detected.Subunits of the vitellins of the ovaries ,ova and nauplius larvae varies in number .This phenomenon might be related to the subunits rearrangement or other modifications.In this experiment ,the purified vitellin was used as antigen to produce antiserum from a rabbit. With the antiserum,vitellogenin was detected in the haemolymph of the mature female prawn.The vitellogenin in the haemolymph was purified with chromatography(DEAE-Cellulose-32) or EDTA- Mg²⁺ precipitation at first,and then purified vitellogenin was obtained with the method of electroelution.The vitellogenin of F.chinensis was also considered a lipo-glyco-phospho-caroprotein.Its molecular weight was 476 ku,pI was 5.2,containing 11.6% oligosaccharides.Three subunits(171 ku,94 ku,80 ku) were detected . Nondisulfide bonds were found in the binding of polypeptide subunits.vitellogenin was more unstable than vitellin during the whole lab process.The vitellin of the crayfish, Procambarus clarkii was also purified with two methods such as chromatography(DEAE-Cellulose-32) and electroelution.It was thought to be a lipo-glyco-phospho-caroprotein too ,and the apparent molecular weight was 481 ku,pI was 5.6,containing 19.8% oligosaccharides.Six subunits (198 ku,176 ku,132 ku,111 ku,92 ku, 82 ku) and one disulfide bridge were found in the binding of polypeptide units.And then comparison of partial biochemical characteristics between the vitellin of F.chinensis andP.clarkii was also conducted.