Cloning and sequencing of the melB gene encoding the melibiose permease of Salmonella typhimurium LT2.
The nucleotide sequence of the melB gene coding for the Na+ (Li+)/melibiose symporter of Salmonella typhimurium LT2 was determined, and its amino acid sequence was deduced. It consists of 1428 bp, corresponding to a protein of 476 amino acid residues (calculated molecular weight 52,800). The amino acid sequence is homologous to that of the melibiose permease of Escherichia coli K12, with 85% identical residues. All, except one, of the amino acid residues that have been reported to be important for cation or substrate recognition in the melibiose permease of E. coli are conserved in the melibiose permease of S. typhimurium. In addition, part of the sequence resembles the lactose permease of Streptococcus thermophilus, the animal glucose transporter (GLUT1), the plasmid-coded raffinose permease (RafB), and the NADH-ubiquinone oxidoreductase chain 4 (Nuo4) of Aspergillus amstelodami.
Mizushima
K
K
Department of Microbiology, Faculty of Pharmaceutical Sciences, Okayama University, Japan.
Awakihara
S
S
Kuroda
M
M
Ishikawa
T
T
Tsuda
M
M
Tsuchiya
T
T
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D003062:Codon; D004271:DNA, Fungal; D004926:Escherichia coli; D026901:Membrane Transport Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010957:Plasmids; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015183:Restriction Mapping; D012486:Salmonella typhimurium / Q000201:enzymology* / Q000235:genetics; D013379:Substrate Specificity; D027981:Symporters
D003062:Codon; D004271:DNA, Fungal; D026901:Membrane Transport Proteins; D011994:Recombinant Proteins; D027981:Symporters; C021548:melibiose permease