Structural Analysis of the Glycine-rich, Arginine-rich Histone

The glycine-rich, arginine-rich (GAR) histone from calf thymus, which contains 1 methionine residue, was cleaved with cyanogen bromide to yield two peptides which were fractionated on Sephadex G-100.2. The smaller peptide was isolated and contained 18 amino acids.This peptide was the carboxyl-terminal portion of the GAR histone since it did not contain homoserine, and aspartic acid was the amino-terminal amino acid.The amino-terminal amino acid of the whole GAR histone is acetylserine.The carboxyl-terminal sequence of the whole GAR histone was found to be Gly-Gly-COOH by treatment with carboxypeptidase which agreed with the carboxyl-terminal sequence of the octadecapeptide.3.This octadecapeptide was found to contain 2 of the 4 tyrosine and 1 of the 2 phenylalanine residues contained in the whole GAR histone.4. The total sequence of this octadecapeptide was determined after tryptic and chymotryptic hydrolysis to be: Asp-Val-Val-Tyr-Ala-Leu-Lys-Arg-Gln-Gly-Arg-Thr-Leu-Tyr-Gly-Phe-Gly-Gly-COOH.