PURIFICATION OF BOVINE BETA(2)-MICROGLOBULIN FROM COLOSTRUM AND ITS COMPLETE AMINO-ACID-SEQUENCE

Bovine beta(2)-microglobulin (beta(2)-m) was purified from colostrum m ilk in two chromatographic steps: anion-exchange chromatography, and g el filtration, The amino acid sequence was determined to confirm that the purified protein was beta(2)-m A molecular weight of 11.8 kDa beta (2)-m was estimated using sodium dodecyl sulfate-polyacrylamide gel el ectrophoresis. Bovine beta(2)-m consists of 98 amino acid residues and contains one disulfide linkage connecting residues 25 and 79, The ami no acid sequence determined by this study is different from a previous ly published sequence at three sites, but agrees with the amino acid s equence from cDNA. Thus, we can conclude that the amino acid sequence determined in this study is correct.