title: L-arabinose transport systems in Escherichia coli K-12.
abstract: Mutations in the arabinose transport operons of Escherichia coli K-12 were isolated with the Mu lac phage by screening for cells in which beta-galactosidase is induced in the presence of L-arabinose. Standard genetic techniques were then used to isolate numerous mutations in either of the two transport systems. Complementation tests revealed only one gene, araE, in the low-affinity arabinose uptake system. P1 transduction placed araE between lysA (60.9 min) and thyA (60.5 min) and closer to lysA. The operon of the high-affinity transport system was found to contain two genes: araF, which codes for the arabinose-binding protein, and a new gene, araG. The newly identified gene, araG, was shown by two-dimensional gel electrophoresis to encode a protein which is located in the membrane. Only defects in araG could abolish uptake by the high-affinity system under the conditions we used.
mesh_terms: D001089:Arabinose / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics; D001692:Biological Transport; D002352:Carrier Proteins / Q000235:genetics; D002874:Chromosome Mapping; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D009154:Mutation
chemical_list: C016242:AraF protein, E coli; D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D001089:Arabinose