title: Isolation and characterization of the Salmonella typhimurium LT2 xylose regulon.
abstract: Salmonella DNA was partially digested with EcoRI, and the digest was fractionated to obtain fragments larger than 8 kilobases (kb). These were ligated into EcoRI-cut pBR322, and the mixture was used to transform Salmonella Xyl- cells selecting for ampR xyl+ transformants. A 21- and a 27-kb plasmid were isolated, both of which contained the entire xylose regulon. The xylose regulon was localized to a 6.3-kb segment of a 13.5-kb EcoRI fragment. Subclones were constructed which contained either the genes for D-xylose isomerase and D-xylulokinase or the genes for the D-xylose transport and the D-xylose regulatory factors. The gene order determined by the subcloning experiments is consistent with that determined by genetic mapping. The spots corresponding to D-xylose isomerase and D-xylulokinase subunits were identified in two-dimensional gels of several xylose-induced strains. Each of them had a molecular weight of 45,000 and an isoelectric point of 6.2 +/- 0.1.
mesh_terms: D019747:Aldose-Ketose Isomerases; D002238:Carbohydrate Epimerases / Q000235:genetics; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D005798:Genes, Bacterial; D005809:Genes, Regulator; D010770:Phosphotransferases / Q000235:genetics; D017853:Phosphotransferases (Alcohol Group Acceptor); D010957:Plasmids; D012486:Salmonella typhimurium / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D014169:Transformation, Bacterial; D014994:Xylose / Q000235:genetics* / Q000378:metabolism
chemical_list: D004269:DNA, Bacterial; D014994:Xylose; D010770:Phosphotransferases; D017853:Phosphotransferases (Alcohol Group Acceptor); C032700:xylulokinase; D002238:Carbohydrate Epimerases; D019747:Aldose-Ketose Isomerases; C023298:xylose isomerase