Phosphatidylcholine transfer protein from porcine liver.

A phosphatidylcholine transfer protein (PC-TP) of porcine liver was purified to exhibit transfer activity similar to that of bovine liver but with different structural properties. By using hydrophobic Phenyl-agarose column as the last purification step, a 1400-fold purification with 20% yield was attained. Comparative studies on the effects of pH, salt, and temperature on the phosphatidylcholine transfer activity revealed that PC-TP from porcine and bovine livers were similar as far as its activity is concerned. However, the amino acid compositions, the molecular weight, and the elution profiles during protein purification for the two proteins are markedly different. It is suggested that the amino acid composition of PC-TP could be significantly altered without changing its activity and specificity.