DNA sequence of the gene scrA encoding the sucrose transport protein EnzymeII(Scr) of the phosphotransferase system from enteric bacteria: homology of the EnzymeII(Scr) and EnzymeII(Bgl) proteins.
The nucleotide sequence of the structural gene, scrA, which codes for sucrose-specific EnzymeII(Scr) (EII(Scr)) of the phosphoenolpyruvate-dependent carbohydrate:phosphotransferase system (PTS), was determined. EllScr requires an EnzymeIII, the product of the gene crr, for full activity. The gene scrA is preceded immediately by a classical Shine-Dalgarno sequence (AAGAGGGTA). It contains 1368 nucleotides with an increased GC-content (58%) corresponding to a polypeptide of 455 amino acid residues (Mr 47,500). The protein has the hydropathic profile (average hydropathy +0.82) of an integral membrane protein lacking extended alpha-helical structures and a signal peptide. Comparison with the sequence of the beta-glucoside-specific EnzymeII (EII(Bgl), 625 amino acids, Mr 66,480; Bramley and Kornberg, 1987a; Schnetz et al., 1987) revealed strong homologies between EiI(Scr) and the first 458 residues of EII(Bgl). The 162 carboxyterminal residues of EII(Bgl), however, showed a high homology with the sequence of EnzymeIII (Nelson et al., 1984), a homology also described recently by Bramley and Kornberg (1987b). The evolutionary and functional significance of the similarities with four other EnzymesII is discussed.
Ebner
R
R
Fachbereich Biologie/Chemie, Universität Osnabrück, FRG.
Lengeler
J W
JW
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D005796:Genes; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid
D004269:DNA, Bacterial; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C055701:phosphoenolpyruvate-sucrose phosphotransferase