Apocarboxypeptidase B-sepharose: a specific adsorbent for peptides.

Apocarboxypeptidase B-Sepharose was prepared by immobilization of porcine carboxypeptidase B, followed by treatment of the column with o-phenanthrolin. This column efficiently adsorbed Met-enkephalin-Arg-Arg (YGGFMRR) in an optimum pH range of 6.5-7.5. The adsorbed Met-enkephalin-Arg-Arg was eluted at pH 4.0 and confirmed to be unaltered. In the apocarboxypeptidase B-Sepharose chromatography, Met-enkephalin-Arg-Arg or dynorphin 1-13 (YGGFLRRIRPKLK), substrates of carboxypeptidase B, was separated from Met-enkephalin (YGGFM), dynorphin B 1-9 (YGGFLRRQF), and beta-neo-endorphin (YGGFLRKYP) which do not react with the immobilized enzyme.