title: Sequence of gene malG in E. coli K12: homologies between integral membrane components from binding protein-dependent transport systems.
abstract: The MalG protein is needed for the transport of maltose in Escherichia coli K12. We present the sequence of gene malG. The deduced amino acid sequence corresponds to a protein of 296 amino acid residues (mol. wt. = 32 188 daltons). This protein is largely hydrophobic (hydrophobic index = 0.83) and is thus presumably an integral inner membrane protein which could span the membrane through six hydrophobic segments. We provide direct evidence from fusion proteins for the translation frame and we also identified the in vitro made MalG protein. We have found a sequence which is highly conserved between MalG and MalF, the other integral inner membrane protein of the maltose transport system. This conserved sequence is also present in all known integral membrane proteins of binding protein-dependent transport systems, always at the same distance (approximately 90 residues) from their COOH terminus. We discuss briefly this finding.
mesh_terms: D018528:ATP-Binding Cassette Transporters; D000595:Amino Acid Sequence; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics*; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins; D005796:Genes; D005798:Genes, Bacterial; D005838:Genotype; D058619:Maltose-Binding Proteins; D008565:Membrane Proteins / Q000235:genetics*; D009004:Monosaccharide Transport Proteins; D010957:Plasmids; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity
chemical_list: D018528:ATP-Binding Cassette Transporters; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; C079123:MalG protein, E coli; D058619:Maltose-Binding Proteins; D008565:Membrane Proteins; D009004:Monosaccharide Transport Proteins; C461599:maltose transport system, E coli; D004262:DNA Restriction Enzymes