Abstract
In this study, bovine β2-m was purified from urine by ion-exchange chromatography and gel chromatography, and the characteristics were compared with those of colostral β2-m by the immunological reactivity, isoelectric points, peptide map, and amino acid sequence. The characteristics of purified urinary β2-m were consistent with those of the colostral β2-m. The urinary and colostral β2-m possessed the same polypeptide chain consisting of 98 amino acids, and its molecular weight is 11.8 kDa. Furthermore, four isoforms of β2-m were found. The isoelectric points were different from each other.
