Abstract
A hog intestinal receptor for intrinsic factor-vitamin B_<12> complex was purified by combined affinity chromatography, gel filtration and isoelectric focusing. The final product had the specific activity of 2,480pg vitamin B_<12> binding through intrinsic factor/mg protein and the recovery was 62.5%. Sodium dodecylsulfate polyacrylamide gel electrophoresis showed main protein bands corresponding to molecular weight of 470,000 and 222,000 in the absence or presence of a reducing agent respectively. Rabbit anti-serum which had been produced against the purified receptor preparation bound receptor-intrinsic factor-vitamin B_<12> to form a macromolecular complex. Fluorescein antibody technique by the sandwich method using the anti-serum showed that the receptor was localized both in the proximal and distal portion of the intestine but neither in the stomach nor in the liver.
