Abstract:
:The ferric uptake regulator (Fur) protein is known to act as a Fe2+-dependent transcriptional repressor of bacterial promoters. Here, we show that, in Helicobacter pylori, Fur can mediate the regulation of iron-activated genes in contrast to classical Fur regulation, in which iron acts as a co-repressor. Inactivation of the fur gene in the chromosome of H. pylori resulted in the derepression of a 19 kDa protein that was identified by N-terminal sequencing as the non-haem-containing ferritin (Pfr). Growth of the wild-type H. pylori strain on media treated with increasing concentrations of FeSO4 resulted in induction of transcription from the Ppfr promoter and, conversely, depletion of iron resulted in repression of Ppfr, indicating that this promoter is iron activated. In the fur mutant, the Ppfr promoter is constitutively highly expressed and no longer responds to iron, indicating that the Fur protein mediates this type of iron regulation. Footprinting analysis revealed that Fur binds to the Ppfr promoter region and that Fe2+ decreases the efficiency of binding. In contrast, Fe2+ increased the affinity of Fur for a classical Fur-regulated promoter, the iron-repressed frpB gene promoter. To our knowledge, this is the first evidence of direct interaction between the Fur protein and the promoter of an iron-activated (-derepressed) gene. Our results support a model in which the iron status of the Fur protein differentially alters its affinity for operators in either iron-repressed or iron-activated genes.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Delany I,Spohn G,Rappuoli R,Scarlato Vdoi
10.1046/j.1365-2958.2001.02696.xsubject
Has Abstractpub_date
2001-12-01 00:00:00pages
1297-309issue
5eissn
0950-382Xissn
1365-2958pii
2696journal_volume
42pub_type
杂志文章abstract::Neisseria gonorrhoeae homologues of gyrA and parC have been identified using hybridization probes generated from conserved regions of diverse gyrA genes. These genes have been tentatively identified as gyrA and parC, based on predicted amino acid sequence homologies to known GyrA homologues from numerous bacterial spe...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1994.tb01297.x
更新日期:1994-10-01 00:00:00
abstract::Restart of arrested replication forks is an important process and PriA, the main Escherichia coli replication restart protein, is essential for viability under any condition that increases the frequency of fork arrest. In priA mutant, replication forks are arrested by spontaneously occurring roadblocks and blocked rep...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2004.03997.x
更新日期:2004-04-01 00:00:00
abstract::The reversible yeast-hyphae transition of the human fungal pathogen Candida albicans is tightly linked to its pathogenicity. In this study, we show that histone H2B mono-ubiquitination (H2Bub) at lysine 123 was maintained at a low level in the yeast state, whereas it increased significantly during yeast-to-hyphae tran...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.14619
更新日期:2020-10-03 00:00:00
abstract::Conjugative transfer of toxin and antibiotic resistance plasmids in Clostridium perfringens is mediated by the tcp conjugation locus. Surprisingly, neither a relaxase gene nor an origin of transfer (oriT) has been identified on these plasmids, which are typified by the 47 kb tetracycline resistance plasmid pCW3. The t...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.13270
更新日期:2016-03-01 00:00:00
abstract::NADPH oxidases (Nox) produce reactive oxygen species (ROS) in multicellular eukaryotic organisms. They trigger defense reactions ('oxidative burst') - in phagocytes and plant cells -, and are involved in a broad range of differentiation processes. Fungal Nox-complexes play a central role in vegetative, sexual and path...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.13391
更新日期:2016-07-01 00:00:00
abstract::The major anionic phospholipids of Escherichia coli, phosphatidylglycerol (PG) and cardiolipin (CL), have been considered to be indispensable for essential cellular functions, such as the initiation of DNA replication and translocation of proteins across the cytoplasmic membrane. However, we successfully constructed a...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1046/j.1365-2958.2001.02320.x
更新日期:2001-03-01 00:00:00
abstract::AtzR is a LysR-type regulator responsible for activation of the cyanuric acid utilization operon atzDEF. AtzR binds the PatzDEF promoter region at a strong recognition element, designated the repressor binding site, and a weaker binding determinant, the activator binding site (ABS). AtzR activates transcription in res...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2010.07100.x
更新日期:2010-04-01 00:00:00
abstract::Oligomerization of the initiator protein, DnaA, on the origin of replication (oriC) is crucial for initiation of DNA replication. Studies in Escherichia coli (Gram-negative) have revealed that binding of DnaA to ATP, but not hydrolysis of ATP, is sufficient to promote DnaA binding, oligomerization and DNA strand separ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2006.05068.x
更新日期:2006-03-01 00:00:00
abstract::The flagellar genes of Caulobacter crescentus are expressed under cell-cycle control. Expression is regulated by both flagellar assembly cues and cell-cycle events. In this paper we define the sequences required for the expression of the flgF operon, a new class of sigma 54 flagellar promoter. This promoter type is ex...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1995.tb02300.x
更新日期:1995-04-01 00:00:00
abstract::The K1 killer toxin of Saccharomyces cerevisiae consists of 103- and 83-residue alpha and beta components whose derivation, from a 316-residue precursor preprotoxin, requires processing at the alpha N-terminus (after ProArg-44), the alpha C-terminus (after ArgArg-149) and at the beta N-terminus (after LysArg-233). The...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1992.tb01496.x
更新日期:1992-02-01 00:00:00
abstract::Lactose is an abundant dietary carbohydrate metabolized by the dental pathogen Streptococcus mutans. Lactose metabolism presents both classic diauxic behaviors and long-term memory, where the bacteria can pause for >11 h before initiating growth on lactose. Here, we explored mechanisms contributing to unusual aspects ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.14597
更新日期:2020-09-03 00:00:00
abstract::Reversible phase variation between the rugose and smooth colony variants is predicted to be important for the survival of Vibrio cholerae in natural aquatic habitats. Microarray expression profiling studies of the rugose and smooth variants of the same strain led to the identification of 124 differentially regulated g...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2004.04154.x
更新日期:2004-07-01 00:00:00
abstract::Erwinia chrysanthemi, a phytopathogenic bacterium, produces a protease inhibitor which is a low-molecular-weight, heat-stable protein. In addition to its action on the three E. chrysanthemi extracellular proteases A, B and C, it also strongly inhibits the 50 kD extracellular protease of Serratia marcescens. Its struct...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1989.tb00106.x
更新日期:1989-01-01 00:00:00
abstract::In Pseudomonas aeruginosa three type VI secretion systems (T6SSs) coexist, called H1- to H3-T6SSs. Several T6SS components are proposed to be part of a macromolecular complex resembling the bacteriophage tail. The T6SS protein HsiE1 (TagJ) is unique to the H1-T6SS and absent from the H2- and H3-T6SSs. We demonstrate t...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2012.08204.x
更新日期:2012-10-01 00:00:00
abstract::Proteic toxin-antitoxin (TA) loci were first identified in bacterial plasmids, and they were regarded as involved in stable plasmid maintenance by a so-called 'addiction' mechanism. Later, chromosomally encoded TA loci were identified and their function ascribed to survival mechanisms when bacteria were subjected to s...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2006.05027.x
更新日期:2006-02-01 00:00:00
abstract::Protein kinase C constitutes a family of serine-threonine kinases found in all eukaryotes and implicated in a wide range of cellular functions, including regulation of cell growth, cellular differentiation and immunity. Here, we present three independent lines of evidence which indicate that protein kinase C is essent...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.13132
更新日期:2015-10-01 00:00:00
abstract::Prokaryotes protect their genomes from foreign DNA with a diversity of defence mechanisms, including a widespread restriction-modification (R-M) system involving phosphorothioate (PT) modification of the DNA backbone. Unlike classical R-M systems, highly partial PT modification of consensus motifs in bacterial genomes...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12692
更新日期:2014-08-01 00:00:00
abstract::The flow of information from the outside to the inside of bacterial cells is largely directed by protein kinases. In addition to histidine/aspartate phosphorelays of two-component response regulators, recent work in Mycobacterium tuberculosis (Mtb) reinforces the idea that phosphorylation on serine (Ser), threonine (T...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1111/mmi.12747
更新日期:2014-10-01 00:00:00
abstract::A growing class of proteins regulates transcription through interaction with DNA-dependent RNA polymerase. Here we report that a recently identified, highly conserved sporulation gene ylyA encodes a novel RNA polymerase-binding protein that influences the expression of genes under the control of the late-acting, sporu...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12262
更新日期:2013-07-01 00:00:00
abstract::Virstatin is a previously described small molecule inhibitor of Vibrio cholerae virulence. We have demonstrated that the molecule inhibits the activity of the transcriptional activator ToxT, thereby preventing elaboration of the toxin co-regulated pilus (TCP) and cholera toxin in vitro and in vivo in O1 strains of V. ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2007.05984.x
更新日期:2007-12-01 00:00:00
abstract::Reversible protein acetylation is established as a modification of major regulatory significance. In particular, histone acetylation regulates access to genetic information in eukaryotes. For example, class I and class II histone deacetylases are regulatory components of corepressor complexes involved in cell cycle pr...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2002.03018.x
更新日期:2002-07-01 00:00:00
abstract::The volume of electron flow through the cbb3 branch of the electron transport chain and the redox state of the quinone pool generate signals that regulate photosynthesis gene expression in Rhodobacter sphaeroides. An inhibitory signal is generated at the level of the catalytic subunit of the cbb3 cytochrome c oxidase ...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1111/j.1365-2958.2001.02299.x
更新日期:2001-03-01 00:00:00
abstract::We have isolated RNA polymerase from Mycobacterium smegmatis and established conditions for specific transcription initiation in vitro. The M. smegmatis enzyme has a strong dependence on supercoiling of the DNA substrate for transcription from mycobacterial promoters. We also show that RNA polymerase is the target for...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1993.tb01572.x
更新日期:1993-04-01 00:00:00
abstract::The recently identified recA gene of the naturally transformable bacterium Streptococcus pneumoniae has been further characterized by constructing a recA null mutation and by investigating its regulation. The recA mutation has been shown to confer both DNA repair (as judged from sensitivity to u.v. and methyl methane ...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1995.tb02250.x
更新日期:1995-01-01 00:00:00
abstract::The availability of nutrients is a major determinant for the timing of morphogenesis and antibiotic production in the soil-dwelling bacterium Streptomyces coelicolor. Here we show that N-acetylglucosamine transport, the first step of an important nutrient signalling cascade, is mediated by the NagE2 permease of the ph...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2009.07020.x
更新日期:2010-03-01 00:00:00
abstract::The bacterial enhancer binding proteins (bEBP) are members of the AAA+ protein family and have a highly conserved 'DE' Walker B motif thought to be involved in the catalytic function of the protein with an active role in nucleotide hydrolysis. Based on detailed structural data, we analysed the functionality of the con...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2007.05901.x
更新日期:2007-11-01 00:00:00
abstract::N15 is a bacteriophage of Escherichia coli that resembles lambda, but, unlike lambda, it lysogenizes as a linear plasmid. We show that stable maintenance of this unusual plasmid-prophage depends on the parA and parB genes, relatives of the partition genes of F and P1 plasmids. ParB of N15, like its F- and P1-encoded h...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2001.02632.x
更新日期:2001-10-01 00:00:00
abstract::The surface of Trypanosoma brucei is covered by a dense coat of glycosylphosphatidylinositol-anchored glycoproteins. The major component is the variant surface glycoprotein (VSG) which is glycosylated by both paucimannose and oligomannose N-glycans. Surface glycans are poorly accessible and killing mediated by peptide...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/mmi.12359
更新日期:2013-11-01 00:00:00
abstract::Chemotactic adaptation to persisting stimulation involves reversible methylation of the chemoreceptors that form complexes with the histidine kinase CheA at a cell pole. The methyltransferase CheR targets to the C-terminal NWETF sequence of the chemoreceptor. In contrast, localization of the methylesterase CheB is lar...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2004.04176.x
更新日期:2004-08-01 00:00:00
abstract::Initial observations that the budding yeast Saccharomyces cerevisiae can be induced to undergo a form of cell death exhibiting typical markers of apoptosis has led to the emergence of a thriving new field of research. Since this discovery, a number of conserved pro- and antiapoptotic proteins have been identified in y...
journal_title:Molecular microbiology
pub_type: 杂志文章,评审
doi:10.1111/j.1365-2958.2006.05486.x
更新日期:2006-12-01 00:00:00