title: Transport and catabolism of D-fructose by Spirillum itersomii.
abstract: Spirillum itersonii ATCC 12639 utilized d-fructose but neither d-glucose nor d-gluconate as a sole source of carbon and energy. The substrate saturation kinetics for d-fructose and d-glucose uptake by whole cells indicated the presence of a carrier-mediated transport system for d-fructose but not for d-glucose. The d-fructose uptake activity was induced (10- to 12-fold increase) during growth on d-fructose-Casamino Acids (CA) or d-glucose-CA medium, but not CA alone. d-Fructose uptake activity was stimulated by Na(+) or Li(+), but was inhibited by KCN, NaN(3), 2,4-dinitrophenol, and p-chloromercuribenzoate. High specific activities of glucokinase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydratase, and 2-keto-3-deoxy-6-phosphogluconate aldolase were detected in extracts of cells cultured on d-fructose-CA medium. These enzymatic activities were undetectable in extracts of cells grown in CA or succinate-CA medium. No decrease in the maximally induced specific activities of these enzymes occurred after the addition of succinate to cells during exponential growth on d-fructose-CA. Fructose 1,6-diphosphate aldolase and glucose-6-phosphate isomerase specific activities were approximately the same irrespective of cultural conditions. These results indicated that d-glucose was not utilized by cells of S. itersonii because this bacterium was impermeable to this hexose.
mesh_terms: D000429:Alcohol Oxidoreductases / Q000378:metabolism; D000446:Aldehyde-Lyases / Q000378:metabolism; D002250:Carbon Radioisotopes; D002474:Cell-Free System; D002729:Chloromercuribenzoates / Q000494:pharmacology; D003470:Culture Media; D003486:Cyanides / Q000494:pharmacology; D004790:Enzyme Induction; D005632:Fructose / Q000378:metabolism*; D005634:Fructose-Bisphosphate Aldolase / Q000378:metabolism; D005941:Glucokinase / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D005956:Glucose-6-Phosphate Isomerase / Q000378:metabolism; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism; D006836:Hydro-Lyases / Q000378:metabolism; D008094:Lithium / Q000494:pharmacology; D009566:Nitrates / Q000494:pharmacology; D010734:Phosphogluconate Dehydrogenase / Q000378:metabolism; D012964:Sodium / Q000494:pharmacology; D013053:Spectrophotometry; D013139:Spirillum / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D013237:Stereoisomerism; D013386:Succinates / Q000378:metabolism
chemical_list: D002250:Carbon Radioisotopes; D002729:Chloromercuribenzoates; D003470:Culture Media; D003486:Cyanides; D009566:Nitrates; D013386:Succinates; D005632:Fructose; D008094:Lithium; D012964:Sodium; D000429:Alcohol Oxidoreductases; D010734:Phosphogluconate Dehydrogenase; D005954:Glucosephosphate Dehydrogenase; D005941:Glucokinase; D000446:Aldehyde-Lyases; D005634:Fructose-Bisphosphate Aldolase; D006836:Hydro-Lyases; D005956:Glucose-6-Phosphate Isomerase; D005947:Glucose