title: The leucine binding proteins of Escherichia coli as models for studying the relationships between protein structure and function.
abstract: The genes encoding the leucine binding proteins in E coli have been cloned and their DNA sequences have been determined. One of the binding proteins (LIV-BP) binds leucine, isoleucine, valine, threonine, and alanine, whereas the other (LS-BP) binds only the D- and L-isomers of leucine. These proteins bind their solutes as they enter the periplasm, then interact with three membrane components, livH, livG, and livM, to achieve the translocation of the solute across the bacterial cell membrane. Another feature of the binding proteins is that they must be secreted into the periplasmic space where they carry out their function. The amino acid sequence of the two binding proteins is 80% homologous, indicating that they are the products of an ancestral gene duplication. Because of these characteristics of the leucine binding proteins, we are using them as models for studying the relationships between protein structure and function.
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D001692:Biological Transport; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002874:Chromosome Mapping; D029968:Escherichia coli Proteins; D005796:Genes; D005798:Genes, Bacterial; D007930:Leucine / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008954:Models, Biological; D033902:Periplasmic Binding Proteins; D011487:Protein Conformation; D013329:Structure-Activity Relationship
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; C488923:LivJ protein, E coli; C024913:LivK protein, E coli; D008565:Membrane Proteins; D033902:Periplasmic Binding Proteins; C028332:leucine-isoleucine-valine binding protein, bacteria; D007930:Leucine