Partial characterization of serum immunoglobulins of Oreochromis mossambicus.

Serum immunoglobulins of O. mossambicus were purified using chromatography methods--CM affinity gel blue chromatography followed by two step purification involving a combination of ion-exchange and gel filtration chromatography. Studies revealed that O. mossambicus produces only one class of high molecular weight macroglobulin as determined by molecular sieving by Sepharose CL 6-B. Immunoelectrophoresis of purified O. mossambicus serum against rabbit anti O. mossambicus serum gave only a single precipitin line. Further analysis of the immunoglobulin by SDS-PAGE showed that the IgM macroglobulin weighs about 900,000 Da, composed of mu-like heavy chain weighing about 90 kDa each and light chains weighing about 30 kDa each.