title: Inhibition of citric acid accumulation by manganese ions in Aspergillus niger mutants with reduced citrate control of phosphofructokinase.
abstract: Mutant strains of Aspergillus niger with reduced citrate control of carbohydrate catabolism (cic mutants) grow faster than the parent strain on media containing 5% (wt/vol) citrate. The mutants tolerated a higher intracellular citrate concentration than the parent strain. One mutant (cic-7/3) contained phosphofructokinase activity significantly less sensitive towards citrate than the enzyme from the parent strain. When this mutant was grown under citrate-accumulating conditions, acidogenesis was far less sensitive to inhibition by Mn2+ than in the parent strain. Some of the cic mutants also showed altered citrate inhibition of NADP-specific isocitrate dehydrogenase.
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D002951:Citrates / Q000378:metabolism* / Q000494:pharmacology; D019343:Citric Acid; D005947:Glucose / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007521:Isocitrate Dehydrogenase / Q000037:antagonists & inhibitors; D008345:Manganese / Q000494:pharmacology*; D009154:Mutation; D010732:Phosphofructokinase-1 / Q000378:metabolism*; D000644:Quaternary Ammonium Compounds / Q000378:metabolism
chemical_list: D002951:Citrates; D000644:Quaternary Ammonium Compounds; D019343:Citric Acid; D008345:Manganese; D007521:Isocitrate Dehydrogenase; C039355:isocitrate dehydrogenase (NADP+); D010732:Phosphofructokinase-1; D005947:Glucose