title: Streptococcal phosphoenolpyruvate-sugar phosphotransferase system: amino acid sequence and site of ATP-dependent phosphorylation of HPr.
abstract: The amino acid sequence of histidine-containing protein (HPr) from Streptococcus faecalis has been determined by direct Edman degradation of intact HPr and by amino acid sequence analysis of tryptic peptides, V8 proteolytic peptides, thermolytic peptides, and cyanogen bromide cleavage products. HPr from S. faecalis was found to contain 89 amino acid residues, corresponding to a molecular weight of 9438. The amino acid sequence of HPr from S. faecalis shows extended homology to the primary structure of HPr proteins from other bacteria. Besides the phosphoenolpyruvate-dependent phosphorylation of a histidyl residue in HPr, catalyzed by enzyme I of the bacterial phosphotransferase system, HPr was also found to be phosphorylated at a seryl residue in an ATP-dependent protein kinase catalyzed reaction [Deutscher, J., & Saier, M. H., Jr. (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 6790-6794]. The site of ATP-dependent phosphorylation in HPr of S. faecalis has now been determined. [32P]P-Ser-HPr was digested with three different proteases, and in each case, a single labeled peptide was isolated. Following digestion with subtilisin, we obtained a peptide with the sequence -(P)Ser-Ile-Met-. Using chymotrypsin, we isolated a peptide with the sequence -Ser-Val-Asn-Leu-Lys-(P)Ser-Ile-Met-Gly-Val-Met-. The longest labeled peptide was obtained with V8 staphylococcal protease. According to amino acid analysis, this peptide contained 36 out of the 89 amino acid residues of HPr. The following sequence of 12 amino acid residues of the V8 peptide was determined: -Tyr-Lys-Gly-Lys-Ser-Val-Asn-Leu-Lys-(P)Ser-Ile-Met-.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000302:isolation & purification / Q000378:metabolism*; D001665:Binding Sites; D013293:Enterococcus faecalis / Q000201:enzymology*; D010446:Peptide Fragments / Q000032:analysis; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000302:isolation & purification / Q000378:metabolism*; D010766:Phosphorylation
chemical_list: D001426:Bacterial Proteins; D010446:Peptide Fragments; D000255:Adenosine Triphosphate; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C030182:phosphocarrier protein HPr