title: Atypical genetic locus associated with the zwf gene encoding the glucose 6-phosphate dehydrogenase from Enterococcus mundtii CRL35.
abstract: The zwf gene encoding glucose 6-phosphate dehydrogenase (G6PD, EC.1.1.1.49) from Enterococcus mundtii CRL35 was cloned as a 4921 bp EcoRI fragment and analyzed. The predicted zwf gene product consists of 506 residues with a molecular mass of 58.4 kDa, and is fully active in Escherichia coli as demonstrated by its heterologous expression in the zwf-negative mutant E. coli Su294. It shows a high degree of sequence identity (40-60%) to G6PDs described in other bacteria. Upstream of the zwf gene, a homolog of the DtxR family was identified (ORF D). Analysis of the 5' sequence of ORF D revealed a potential promoter sequence, which would suggest the presence of an operon-like structure between ORF D and the zwf gene. Finally, it was found that Fe2+ levels have an important role as a modulator of G6PD activity. This is the first report of this type of regulation of G6PD activity. A possible involvement in oxidative stress is discussed.
authors.affiliation: Centro de Referencia para Lactobacilos (CONICET), Chacabuco , 145 (4000), Tucumán, Argentina.
authors.forename: Lucila
authors.initials: L
authors.lastname: Saavedra
authors.forename: Fernando
authors.initials: F
authors.lastname: Sesma
mesh_terms: D016983:Enterococcus / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism; D005296:Ferrous Compounds / Q000378:metabolism; D016680:Genome, Bacterial; D005954:Glucosephosphate Dehydrogenase / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009876:Operon; D018384:Oxidative Stress
chemical_list: D005296:Ferrous Compounds; D005954:Glucosephosphate Dehydrogenase