title: Functional expression of the Acanthamoeba castellanii alternative oxidase in Escherichia coli; regulation of the activity and evidence for Acaox gene function.
abstract: To evidence Acanthamoeba castellanii alternative oxidase (AcAOX) gene product function, we studied alterations in the levels of mRNA and protein and AcAOX activity during growth in amoeba batch culture. Moreover, heterologous expression of AcAOX in AOX-deficient Escherichia coli confirmed by the protein immunodetection and functional studies was performed. Despite the presence of native bo and bd quinol oxidases in E. coli membrane, from which the latter is known to be cyanide-resistant, functional expression of AcAOX in E. coli conferred cyanide-resistant benzohydroxamate-sensitive respiration on the bacteria. Moreover, AcAOX activity in transformed bacteria was stimulated by GMP and inhibited by ATP, indicating that AcAOX is regulated by mutual exclusion of purine nucleotides, which was previously demonstrated in the mitochondria of A. castellanii.
authors.affiliation: Department of Bioenergetics, Adam Mickiewicz University, Umultowska 89, 61-614 Poznan, Poland.
authors.forename: Nina
authors.initials: N
authors.lastname: Antos-Krzeminska
authors.forename: Wieslawa
authors.initials: W
authors.lastname: Jarmuszkiewicz
mesh_terms: D048248:Acanthamoeba castellanii / Q000201:enzymology* / Q000235:genetics; D004789:Enzyme Activation / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D024101:Mitochondrial Proteins / Q000096:biosynthesis* / Q000235:genetics* / Q000378:metabolism; D010088:Oxidoreductases / Q000096:biosynthesis* / Q000235:genetics* / Q000378:metabolism; D010940:Plant Proteins / Q000096:biosynthesis* / Q000235:genetics* / Q000378:metabolism; D000099188:Alternative Oxidase
chemical_list: D024101:Mitochondrial Proteins; D010088:Oxidoreductases; D010940:Plant Proteins; D000099188:Alternative Oxidase
keywords: Acanthamoeba castellanii; alternative oxidase; cyanide-resistant respiration; expression fonctionnelle chez E. coli; functional expression in E. coli; mitochondria; mitochondrie; oxydase alternative; respiration résistante au cyanure