Immunochemical and Biochemical Studies Demonstrating the Identity of a Bovine Spinal Cord Protein (Scp) and a Basic Protein of Bovine Peripheral Myelin (Bf)

A protein extracted from bovine peripheral myelin (BF) and a protein extracted from bovine spinal cord (SCP) have been shown to be identical: the proteins cross‐react immunochemicaliy with each other but not with highly purified CNS myelin basic protein. Neither BF nor SCP have anti‐encephalitogenic activity. Their electrophoretic behavior is the same at three different pH values. Their apparent molecular weight by sodium dodecyl sulfate‐gel electrophoresis is 13,800 ± 550. The amino acid compositions of the proteins are essentially identical. BF and SCP each contain 2 cysteine residues and have valine at the C terminus. The 23 major tryptic peptides are identical on peptide maps. Circular dichroic analyses yield essentially identical curves, which, when computed by best‐fit curve analysis, indicate that each has 0%α helix and a large percentage of β structure.