title: Effect of cadmium and copper on the production of citric acid by Aspergillus niger.
abstract: Copper and cadmium inhibited the growth as well as citric acid production (depending on the heavy metal concentrations) by citric-acid-producing Aspergillus niger. Activity of citrate synthase was connected with citrate synthesis in the absence as well as in the presence of heavy metals. The activity of aconitase, and both NAD- and NADP-isocitrate dehydrogenases was strongly inhibited by copper. The contents of DNA and proteins in the cells decreased but the contents of lipids and polysaccharides increased considerably in the presence of both heavy metals.
authors.affiliation: Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria.
authors.forename: K
authors.initials: K
authors.lastname: Tsekova
authors.forename: D
authors.initials: D
authors.lastname: Dentchev
authors.forename: D
authors.initials: D
authors.lastname: Todorova
mesh_terms: D000154:Aconitate Hydratase / Q000378:metabolism; D001234:Aspergillus niger / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D002104:Cadmium / Q000494:pharmacology*; D002950:Citrate (si)-Synthase / Q000378:metabolism; D019343:Citric Acid / Q000378:metabolism*; D003300:Copper / Q000494:pharmacology*; D003470:Culture Media; D004271:DNA, Fungal / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005656:Fungal Proteins / Q000378:metabolism; D007521:Isocitrate Dehydrogenase / Q000378:metabolism; D050356:Lipid Metabolism; D011134:Polysaccharides / Q000378:metabolism
chemical_list: D003470:Culture Media; D004271:DNA, Fungal; D005656:Fungal Proteins; D011134:Polysaccharides; D002104:Cadmium; D019343:Citric Acid; D003300:Copper; D007521:Isocitrate Dehydrogenase; C039355:isocitrate dehydrogenase (NADP+); D002950:Citrate (si)-Synthase; D000154:Aconitate Hydratase