Biochemical characterization of vitellin from the freshwater prawn Macrobrachium malcolmsonii

Abstract

Vitellin and vitellogenin characterized from mature ovaries, hemolymph, and the hepatopancreas of the freshwater prawn Macrobrachium malcolmsonii using SDS-PAGE revealed that vitellin exists as 89 and 100 kDa subunits, and vitellogenin as 89, 100 and 170 kDa subunits. Vitellogenin polypeptides in the hemolymph and hepatopancreas were present at different maturation stages (early mature, mature, spent), whereas the vitellin polypeptides were correlated with ovarian maturation. Biochemical characterization of the vitellin polypeptides revealed that only the 89 kDa is a lipoglycopolypeptide. Immunological studies using anti-vitellin antisera of M. malcolmsonii using immunodiffusion and western blot further confirmed that the vitellogenin polypeptide consists of 89, 100, and170 kDa subunits in the hepatopancreas and hemolymph, and vitellin polypeptides of 89, 100 kDa subunits in the ovary and egg. The N-terminal amino acid sequence of the first seven amino acids of the 89 kDa subunit of vitellin of M. malcolmsonii has a 29% similarity with that of the freshwater prawn M. rosenbergii, and 14% similarity to vitellin of the marine prawns Litopenaeus merguensis, L. vannamei, the crayfish Cherax quadricarinatus, and Lhobosis rhomboides (pinfish species).