Abstract：
:We have examined the role of the F-plasmid TraV outer membrane lipoprotein in the assembly of F-pili. Yeast two-hybrid analysis with a traV bait repeatedly identified traK, which is predicted to encode a periplasmic protein, among positive prey plasmids. A traK bait in turn identified traV and traB, which is predicted to encode an inner membrane protein. A traB bait exclusively identified traK preys. Several additional observations support the hypothesis that TraV, TraK and TraB form a complex in Escherichia coli that spans the cell envelope from the outer membrane (TraV) through the periplasm (TraK) to the inner membrane (TraB). First, two-hybrid analyses indicated that TraV and TraB bind to different TraK segments, as required if TraK bridges a ternary complex. Secondly, all three proteins fractionated with the E. coli outer membrane in tra+ cells. In contrast, TraB fractionated with the inner membrane in traV or traK mutant cells, and TraK appeared in the osmotic shock fluid from the traV mutant. These results are consistent with a TraV-TraK-TraB complex anchored to the outer membrane via the TraV lipoprotein. Further, in traK mutant cells, TraV failed to accumulate to a detectable level, and the TraB level was significantly reduced, suggesting that TraV and TraB must interact with TraK for either protein to accumulate to its normal level. Both TraK and TraV accumulated in traB2[Am] cells; however, the TraB2 amber fragment could be detected by Western blot, and sequence analysis indicated that the fragment retained the TraK-binding domain suggested by yeast two-hybrid analysis. We propose that TraV is the outer membrane anchor for a trans-envelope, Tra protein structure required for the assembly of F-pili and possibly for other events of conjugal DNA transfer.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Harris RL,Hombs V,Silverman PMdoi
10.1046/j.1365-2958.2001.02667.xsubject
Has Abstractpub_date
2001-11-01 00:00:00pages
757-66issue
3eissn
0950-382Xissn
1365-2958pii
2667journal_volume
42pub_type
杂志文章abstract：:Salmonella enterica subspecies I serotypes are responsible for the vast majority of salmonellosis in mammals and birds, yet only a few factors specific to this group that allow them to persist in this niche have been identified. We show that STM0557, a S. enterica subspecies I-specific gene encoding an inner membrane ...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2008.06461.x
更新日期：2008-12-01 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：:Malaria transmission requires that the parasites differentiate into gametocytes prior to ingestion by a mosquito during a blood meal. Once in the mosquito midgut the gametocytes emerge from red blood cells (RBCs), fertilize, develop into ookinetes and finally infectious sporozoites. Gamete surface antigen, Pfs230, is ...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2006.05284.x
更新日期：2006-08-01 00:00:00
abstract：:The fitness of host-associated microbes depends on their ability to access nutrients in vivo. Identifying these mechanisms is significant for understanding how microbes have evolved to fill specific ecological niches within a host. Vibrio fischeri is a bioluminescent bacterium that colonizes and proliferates within th...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/mmi.14177
更新日期：2019-03-01 00:00:00
abstract：:The interactions between pathogenic bacteria and the host need to be resolved at the molecular level in order to develop novel vaccines and drugs. We have previously identified strepadhesin, a novel glycoprotein-binding activity in Streptococcus pyogenes, which is regulated by Mga, a regulator of streptococcal virulen...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2001.02269.x
更新日期：2001-01-01 00:00:00
abstract：:A novel two-component system (TCS) designated as DraR-K (sco3063/sco3062) was identified to be involved in differential regulation of antibiotic biosynthesis in Streptomyces coelicolor. The S. coelicolor mutants with deletion of either or both of draR and draK exhibited significantly reduced actinorhodin (ACT) but inc...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2012.08126.x
更新日期：2012-08-01 00:00:00
abstract：:During Bacillus subtilis endospore formation, a complex protein coat is assembled around the maturing spore. The coat is made up of more than two dozen proteins that form an outer layer, which provides chemical resistance, and an inner layer, which may play a role in the activation of germination. A third, amorphous l...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1997.mmi532.x
更新日期：1997-09-01 00:00:00
abstract：:The group A streptococcus (GAS) causes a variety of human diseases, including toxic shock syndrome and necrotizing fasciitis, which are both associated with significant mortality. Even the superficial self-limiting diseases caused by GAS, such as pharyngitis, impose a significant economic burden on society. GAS can ca...
journal_title：Molecular microbiology
pub_type： 杂志文章,评审
doi：10.1111/j.1365-2958.2007.05649.x
更新日期：2007-04-01 00:00:00
abstract：:The nucleotide sequence of trkA, a gene encoding a surface component of the constitutive K(+)-uptake systems TrkG and TrkH from Escherichia coli, was determined. The structure of the TrkA protein deduced from the nucleotide sequence accords with the view that TrkA is peripherally bound to the inner side of the cytopla...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1993.tb01714.x
更新日期：1993-08-01 00:00:00
abstract：:Sensory adaptation of low-abundance chemoreceptors in Escherichia coli requires assistance from high-abundance receptors, because only high-abundance receptors carry the carboxyl-terminal pentapeptide sequence NWETF that enhances adaptational covalent modification. Using membrane vesicles containing both high-abundanc...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2005.04641.x
更新日期：2005-06-01 00:00:00
abstract：:The small RNA, ArcZ (previously RyhA/SraH), was discovered in several genome-wide screens in Escherichia coli and Salmonella. Its high degree of genomic conservation, its frequent recovery by shotgun sequencing, and its association with the RNA chaperone, Hfq, identified ArcZ as an abundant enterobacterial 'core' smal...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2009.06857.x
更新日期：2009-10-01 00:00:00
abstract：:The pathogen Vibrio cholerae modulates the expression of many genes in order to transition from its environmental reservoir to its niche in the human host. Among these are genes encoding two related Type IV pili, the mannose-sensitive haemagglutinin (MSHA) pilus, which aids V. cholerae persistence in aquatic environme...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2007.06091.x
更新日期：2008-02-01 00:00:00
abstract：:The development of new drugs for treating Pneumocystis carinii infections in AIDS patients is hampered by the lack of long-term culture systems, and by our generally limited knowledge of this organism. Recently, however, we observed significant activity of various benzimidazoles against growth of this organism in shor...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1992.tb02204.x
更新日期：1992-11-01 00:00:00
abstract：:Quinone-based compounds have been exploited to treat infectious diseases and cancer, with such chemicals often functioning as inhibitors of key metabolic pathways or as prodrugs. Here, we screened an aziridinyl 1,4-benzoquinone (ABQ) library against the causative agents of trypanosomiasis, and cutaneous leishmaniasis,...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/mmi.13767
更新日期：2017-10-01 00:00:00
abstract：:While examining the molecular basis for the lack of actin-based motility for the non-pathogenic spotted fever group (SFG) R. peacockii, we identified a novel insertion sequence (IS) element, ISRpe1, disrupting the coding sequence of rickA, demonstrated to induce actin-tail polymerization for the SFG rickettsiae. This ...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2005.04806.x
更新日期：2005-10-01 00:00:00
abstract：:Fungi defend their ecological niche against antagonists by producing antibiosis molecules. Some of these molecules are only produced upon confrontation with the antagonist. The basidiomycete Coprinopsis cinerea induces the expression of the sesquiterpene synthase-encoding gene cop6 and its two neighboring genes coding...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/mmi.14277
更新日期：2019-08-01 00:00:00
abstract：:Regions close to the replication terminus of the Escherichia coli chromosome are strongly refractory to genomic inversions. Since these regions also harbour polar replication terminator-like sequences or pause sites, we have investigated the possibility that slowing of replication as a result of pausing at inverted pa...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1990.tb00621.x
更新日期：1990-04-01 00:00:00
abstract：:In vivo and in vitro analyses indicate that transcription of the argO gene coding for an arginine exporter is regulated by the global transcriptional regulator Lrp, an effect that went by unnoticed in previous genome-scale screenings of the Lrp regulatory network in Escherichia coli. Lrp activates the argO promoter fo...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2009.06950.x
更新日期：2009-12-01 00:00:00
abstract：:The csiD-ygaF-gabDTP region in the Escherichia coli genome represents a cluster of sigma S-controlled genes. Here, we investigated promoter structures, sigma factor dependencies, potential co-regulation and environmental regulatory patterns for all of these genes. We find that this region constitutes a complex operon ...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2003.03867.x
更新日期：2004-02-01 00:00:00
abstract：:Glutaredoxins and thioredoxins are small heat-stable oxidoreductases that have been conserved throughout evolution. The yeast Saccharomyces cerevisiae contains two gene pairs encoding cytoplasmic glutaredoxins (GRX1, GRX2) and thioredoxins (TRX1, TRX2). We report here that the quadruple trx1 trx2 grx1 grx2 mutant is i...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2000.01948.x
更新日期：2000-06-01 00:00:00
abstract：:A novel growth phase-associated two-component-type regulator, Fas (fibronectin/fibrinogen binding/haemolytic activity/streptokinase regulator), of Streptococcus pyogenes was identified in the M1 genome sequence, based on homologies to the histidine protein kinase (HPK) and response regulator (RR) part of the Staphyloc...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2001.02226.x
更新日期：2001-01-01 00:00:00
abstract：:A histidine kinase, Hik33, appears to sense decreases in temperature and to regulate the expression of certain cold-inducible genes in the cyanobacterium Synechocystis sp. PCC6803. To examine the role of Hik33 in the regulation of gene expression, we analysed a DeltaHik33 mutant using the DNA microarray technique. In ...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2001.02379.x
更新日期：2001-04-01 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：:Experimental evidence suggests that apicomplexan parasites possess bipartite promoters with basal and regulated cis-elements similar to other eukaryotes. Using a dual luciferase model adapted for recombinational cloning and use in Toxoplasma gondii, we show that genomic regions flanking 16 parasite genes, which encomp...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2008.06249.x
更新日期：2008-06-01 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：:Sphingomyelin is the main sphingolipid in Trypanosoma brucei, the causative agent of African sleeping sickness. In vitro and in vivo characterization of the T. brucei neutral sphingomyelinase demonstrates that it is directly involved in sphingomyelin catabolism. Gene knockout studies in the bloodstream form of the par...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2010.07151.x
更新日期：2010-06-01 00:00:00
abstract：:Post-transcriptional repression of porin synthesis has emerged as a major function of Hfq-dependent, small non-coding RNAs (sRNAs). Many enterobacteria express OmpX-like porins, a family of outer membrane proteins whose physiological roles and structural properties have been studied intensively. While regulatory sRNAs...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2008.06189.x
更新日期：2008-05-01 00:00:00
abstract：:We used in vivo oxidative cross-linking of engineered cysteine pairs to assess conformational changes in the four-helix transmembrane domain of chemoreceptor Trg. Extending previous work, we searched for and found a fourth cross-linking pair that spanned the intrasubunit interface between transmembrane helix 1 (TM1) a...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2001.02446.x
更新日期：2001-05-01 00:00:00
abstract：:Each bacterium has to co-ordinate its growth with division to ensure genetic stability of the population. Consequently, cell division and growth are tightly regulated phenomena, albeit different bacteria utilise one of several alternative regulatory mechanisms to maintain control. Here we consider GpsB, which is linke...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/mmi.13279
更新日期：2016-03-01 00:00:00
abstract：:Three u.v.-induced mutants of the purine-cytosine permease gene of Saccharomyces cerevisiae, with altered apparent Michaelis constant of transport (Kmapp), were cloned and sequenced. One of the mutants had extensive nucleotide replacement, whereas the other two had a single mutation. To evaluate the contribution of th...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1992.tb01757.x
更新日期：1992-10-01 00:00:00
