title: Genome diversity of the TetR family of transcriptional regulators in a metal-reducing bacterial family Geobacteraceae and other microbial species.
abstract: Members of the TetR family of bacterial transcriptional regulators affect expression of genes whose products are involved in a variety of important functions, including osmotic stress, catabolic pathways, homeostasis, biosynthesis of antibiotics, expression of efflux pumps, multidrug resistance, and virulence of pathogenic bacteria. We used genome sequence information to carry out phylogenetic classification of 864 TetR family members with a special focus on TetR regulators in Geobacteraceae, an environmentally important family of delta-Proteobacteria. The genome of Geobacter sulfurreducens, a model representative of Geobacteraceae, contains nine genes from the tetR family. Several of these genes are located immediately upstream of operons encoding functionally important c-type cytochromes. Computational analyses identified the presence of conserved promoters and other regulatory binding sites upstream of several G. sulfurreducens tetR genes. This suggests the possibility of an intermediary role of TetR family proteins in Geobacteraceae in regulatory cascades involving a variety of sigma factors. In order to understand the role of the TetR regulatory family in Geobacteraceae, we have inferred phylogenetic relationships among the Geobacteraceae TetR proteins and their homologs in other microbial species.
authors.affiliation: Department of Preventive Medicine, the University of Tennessee Health Science Center, Memphis, USA. jkrushka@uthsc.edu
authors.forename: Julia
authors.initials: J
authors.lastname: Krushkal
authors.forename: Sreedhar
authors.initials: S
authors.lastname: Sontineni
authors.forename: Ching
authors.initials: C
authors.lastname: Leang
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Qu
authors.forename: Ronald M
authors.initials: RM
authors.lastname: Adkins
authors.forename: Derek R
authors.initials: DR
authors.lastname: Lovley
mesh_terms: D001426:Bacterial Proteins / Q000145:classification / Q000235:genetics; D001665:Binding Sites; D006090:Gram-Negative Bacteria / Q000235:genetics / Q000378:metabolism*; D008670:Metals / Q000378:metabolism*; D010084:Oxidation-Reduction; D010802:Phylogeny; D011401:Promoter Regions, Genetic; D012808:Sigma Factor / Q000145:classification / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D008670:Metals; D012808:Sigma Factor