title: Stimulation of the cyanide-resistant alternative respiratory pathway by oxygen in Acremonium chrysogenum correlates with the size of the intracellular peroxide pool.
abstract: The relationship between oxygen input and activity of the cyanide-resistant alternative respiration of submerged cultures of Acremonium crysogenum was investigated. The volumetric oxygen transfer coefficient of the respective cultures correlated positively within almost two ranges of magnitude with the size of the intracellular peroxide pool, which in turn, correlated with the activity of the cyanide-resistant alternative respiratory pathway. Increased aeration also stimulated the glucose uptake rate but had no effect on the total respiration rate or the growth rate. Addition of the lipid peroxyl radical scavenger DL-alpha-tocopherol to A. chrysogenum cultures decreased the rate of intracellular peroxide production as well as glucose uptake. An increase in the cyanide-resistant fraction of total respiration was observed, while growth and the total respiratory activity remained unchanged. We conclude that intracellular peroxides may stimulate the alternative respiration in A. chrysogenum.
authors.affiliation: Department of Microbiology and Biotechnology, Faculty of Science, University of Debrecen, H-4010, P.O. Box 63, Debrecen, Hungary. karaffal@tigris.klte.hu
authors.forename: Levente
authors.initials: L
authors.lastname: Karaffa
authors.forename: Erzsébet
authors.initials: E
authors.lastname: Sándor
authors.forename: Erzsébet
authors.initials: E
authors.lastname: Fekete
authors.forename: József
authors.initials: J
authors.lastname: Kozma
authors.forename: Attila
authors.initials: A
authors.lastname: Szentirmai
authors.forename: István
authors.initials: I
authors.lastname: Pócsi
mesh_terms: D000164:Acremonium / Q000145:classification / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism*; D003470:Culture Media; D003486:Cyanides / Q000378:metabolism / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D025141:Drug Resistance, Fungal; D005947:Glucose / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism* / Q000494:pharmacology; D010545:Peroxides / Q000032:analysis / Q000378:metabolism*; D024502:alpha-Tocopherol / Q000378:metabolism / Q000494:pharmacology
chemical_list: D003470:Culture Media; D003486:Cyanides; D010545:Peroxides; D024502:alpha-Tocopherol; D005947:Glucose; D010100:Oxygen