title: Induction and catabolite repression of L-rhamnose dehydrogenase in Pullularia pullulans.
abstract: The growth of Pullularia pullulans on L-rhamnose (6-deoxy-L-mannose) as the sole carbon source induces the synthesis of L-rhamnose dehydrogenase, a nicotinamide adenine dinucleotide-dependent enzyme that catalyzes the oxidation of the deoxy sugar to L-rhamnonolactone. The enzyme induction is inhibited by cycloheximide, suggesting de novo synthesis. The presence of d-glucose (0.2%) or D-galactose (0.2%) simultaneously with the inducer in the induction medium produced 50% repression of dehydrogenase synthesis, but no effect was detected with D-fructose and D-mannose at the same concentration. High levels of D-glucose (2%), under maximal catabolite repression conditions, produced a complete inhibition of enzyme synthesis.
mesh_terms: D002237:Carbohydrate Dehydrogenases / Q000096:biosynthesis*; D003513:Cycloheximide / Q000494:pharmacology; D004790:Enzyme Induction / Q000187:drug effects; D004794:Enzyme Repression; D005632:Fructose / Q000494:pharmacology; D005690:Galactose / Q000494:pharmacology; D005947:Glucose / Q000494:pharmacology; D008358:Mannose / Q000494:pharmacology; D003904:Mitosporic Fungi / Q000201:enzymology*; D012210:Rhamnose
chemical_list: D005632:Fructose; D003513:Cycloheximide; D002237:Carbohydrate Dehydrogenases; D005947:Glucose; D008358:Mannose; D012210:Rhamnose; D005690:Galactose