Amino acid sequence of ATP phosphoribosyltransferase of Salmonella typhimurium

Abstract

The amino acid sequence of ATP phosphoribosyltransferase [1-(5'-phosphoribosyl)-ATP:pyrophosphate phosphoribosyltransferase, EC 2.4.2.17] of Salmonella typhimurium has been determined. The amino acid sequence analysis was carried out with a combination of manual and automated methods. It was complemented by DNA sequence analysis (done in another laboratory) of the hisG gene, which codes for it. The subunit polypeptide chain contains 299 amino acid residues and has a molecular weight of 33,216. The amino-terminal segment of the protein is relatively basic in character and has limited sequence homologies with the lac repressor and histidinol dehydrogenase. In addition, the protein contains a 40-residue segment that has 13 residues identical with the sequence surrounding the active-site cysteine of glyceraldehyde-3-phosphate dehydrogenase.