title: The thiol-disulfide oxidoreductase system in the cold-adapted bacterium Pseudoalteromonas haloplanktis TAC 125: discovery of a novel disulfide oxidoreductase enzyme.
abstract: In prokaryotes, protein disulfide bond oxidation, reduction and isomerization are catalyzed by members of the thioredoxin superfamily, characterized by the conserved C-X-X-C motif in their active site. Thioredoxins and glutaredoxins contribute to the reducing power in the cytoplasm, while the Dsb system catalyzes disulfide bonds formation in the periplasmic space. This paper addresses the question of disulfide bonds formation in a cold-adapted micro-organism, Pseudoalteromonas haloplanktis TAC 125 (PhTAC125) by characterizing the DsbA system. We found distinctive features respect mesophilic counterparts that highlighted for the first time the occurrence of two adjacent chromosomal DsbA genes organised in a functional operon. The sophisticated transcriptional regulation mechanism that controls the expression of these two genes was also defined. The two DsbA proteins, named PhDsbA and PhDsbA2, respectively, were expressed in Escherichia coli and characterized. Results reported in this paper provide some insights into disulfide bonds formation in a micro organism isolated in the Antarctic sea water.
authors.affiliation: Dipartimento di Chimica Organica e Biochimica, Università di Napoli "Federico II"-Complesso Universitario Monte Sant'Angelo, Via Cynthia, 80126, Napoli, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Madonna
authors.forename: Rosanna
authors.initials: R
authors.lastname: Papa
authors.forename: Leila
authors.initials: L
authors.lastname: Birolo
authors.forename: Flavia
authors.initials: F
authors.lastname: Autore
authors.forename: Nunzianna
authors.initials: N
authors.lastname: Doti
authors.forename: Gennaro
authors.initials: G
authors.lastname: Marino
authors.forename: Eric
authors.initials: E
authors.lastname: Quemeneur
authors.forename: Giovanni
authors.initials: G
authors.lastname: Sannia
authors.forename: Maria L
authors.initials: ML
authors.lastname: Tutino
authors.forename: Angela
authors.initials: A
authors.lastname: Duilio
mesh_terms: D000222:Adaptation, Physiological; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D003080:Cold Temperature; D004269:DNA, Bacterial / Q000235:genetics; D004795:Enzyme Stability; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D011490:Protein Disulfide Reductase (Glutathione) / Q000235:genetics / Q000378:metabolism*; D019704:Protein Disulfide-Isomerases / Q000235:genetics* / Q000378:metabolism*; D031161:Pseudoalteromonas / Q000201:enzymology* / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012623:Seawater / Q000382:microbiology; D017386:Sequence Homology, Amino Acid
chemical_list: D004269:DNA, Bacterial; D011994:Recombinant Proteins; D011490:Protein Disulfide Reductase (Glutathione); D019704:Protein Disulfide-Isomerases