title: Glutathione metabolism of Acremonium chrysogenum in relation to cephalosporin C production: is gamma-glutamyltransferase in the center?
abstract: Methionine increased the intracellular glutathione (reduced) (GSH) pool and the specific gamma-glutamyltransferase (gamma-GT) activity in the cephalosporin C (CPC) producer Acremonium chrysogenum. The accelerated turnover of GSH might be indicative of the existence of a functioning gamma-glutamate cycle, and might supply the CPC biosynthetic machinery with L-cysteine. The gamma-GT was not subject to nitrogen metabolic repression but was more active in cells exposed to different oxidative-stress-generating agents. Exogenous cysteine hindered both the uptake of methionine and the induction of gamma-GT, and was not beneficial for CPC production. There was no causal relationship between the redox status of the cells and the observed cell morphology.
authors.affiliation: Department of Microbiology and Biotechnology, Faculty of Sciences, University of Debrecen, 4010 Debrecen, Hungary.
authors.forename: M A
authors.initials: MA
authors.lastname: Nagy
authors.forename: T
authors.initials: T
authors.lastname: Emri
authors.forename: E
authors.initials: E
authors.lastname: Fekete
authors.forename: E
authors.initials: E
authors.lastname: Sándor
authors.forename: J Y
authors.initials: JY
authors.lastname: Springael
authors.forename: M J
authors.initials: MJ
authors.lastname: Penninckx
authors.forename: I
authors.initials: I
authors.lastname: Pócsi
mesh_terms: D000164:Acremonium / Q000254:growth & development / Q000378:metabolism*; D002511:Cephalosporins / Q000096:biosynthesis*; D015966:Gene Expression Regulation, Fungal; D005978:Glutathione / Q000378:metabolism*; D008715:Methionine / Q000378:metabolism; D018384:Oxidative Stress; D005723:gamma-Glutamyltransferase / Q000378:metabolism*
chemical_list: D002511:Cephalosporins; C025163:cephalosporin C; D008715:Methionine; D005723:gamma-Glutamyltransferase; D005978:Glutathione