Abstract:
:DifA is a methyl-accepting chemotaxis protein (MCP)-like sensory transducer that regulates exopolysaccharide (EPS) production in Myxococcus xanthus. Here mutational analysis and molecular biology were used to probe the signaling mechanisms of DifA in EPS regulation. We first identified the start codon of DifA experimentally; this identification extended the N terminus of DifA for 45 amino acids (aa) from the previous bioinformatics prediction. This extension helped to address the outstanding question of how DifA receives input signals from type 4 pili without a prominent periplasmic domain. The results suggest that DifA uses its N-terminus extension to sense an upstream signal in EPS regulation. We suggest that the perception of the input signal by DifA is mediated by protein-protein interactions with upstream components. Subsequent signal transmission likely involves transmembrane signaling instead of direct intramolecular interactions between the input and the output modules in the cytoplasm. The basic functional unit of DifA for signal transduction is likely dimeric as mutational alteration of the predicted dimeric interface of DifA significantly affected EPS production. Deletions of 14-aa segments in the C terminus suggest that the newly defined flexible bundle subdomain in MCPs is likely critical for DifA function because shortening of this bundle can lead to constitutively active mutations.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Xu Q,Black WP,Nascimi HM,Yang Zdoi
10.1128/JB.00944-10subject
Has Abstractpub_date
2011-02-01 00:00:00pages
759-67issue
3eissn
0021-9193issn
1098-5530pii
JB.00944-10journal_volume
193pub_type
杂志文章abstract::The mutations of eight chemotaxis-deficient strains of Salmonella typhimurium, including five new mutants in strain LT2, were mapped by P22 transduction in relation to various fla mot deletions in S. abortus-equi. Seven recessive che mutations mapped between motB and flaC: three, all nontumbling, the che region I, adj...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.128.3.754-765.1976
更新日期:1976-12-01 00:00:00
abstract::A spontaneous lac+ revertant of an adenylate cyclase deletion strain of Escherichia coli K-12 was isolated and characterized. This revertant, designated strain KC20, exhibited a pleiotropic suppression of the adenylate cyclase defect, with the crp locus being the site of the suppressor mutation. Cyclic adenosine 3',5'...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.147.2.500-508.1981
更新日期:1981-08-01 00:00:00
abstract::Structural studies were carried out on lipoteichoic acids obtained from defatted cells of 10 Bacillus strains by phenol-water partition followed by chromatography on DEAE-Sephacel and Octyl-Sepharose columns. A group of the tested bacteria (group A), Bacillus subtilis, Bacillus licheniformis, and Bacillus pumilus, was...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.167.2.508-516.1986
更新日期:1986-08-01 00:00:00
abstract::The cold-tolerant bacterium Pusillimonas sp. strain T7-7 is able to utilize diesel oils (C5 to C30 alkanes) as a sole carbon and energy source. In the present study, bioinformatics, proteomics, and real-time reverse transcriptase PCR approaches were used to identify the alkane hydroxylation system present in this bact...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.02107-12
更新日期:2013-05-01 00:00:00
abstract::The effects of variations in growth conditions on the penicillin response of Streptococcus faecium ATCC 9790 were studied. Changes in the growth temperature and medium composition were found to cause striking changes in the bacterial generation time, cellular penicillin sensitivity (minimum inhibitory concentration), ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.154.2.916-923.1983
更新日期:1983-05-01 00:00:00
abstract::The repressive effects of exogenous cytidine on growing cells was examined in a specially constructed strain in which the pool sizes of endogenous uridine 5'-diphosphate and uridine 5'-triphosphate cannot be varied by the addition of uracil and/or uridine to the medium. Five enzymes of the pyrimidine biosynthetic path...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.124.2.764-774.1975
更新日期:1975-11-01 00:00:00
abstract::In Escherichia coli, putrescine is metabolized to succinate for use as a carbon and nitrogen source by the putrescine utilization pathway (Puu pathway). One gene in the puu gene cluster encodes a transcription factor, PuuR, which has a helix-turn-helix DNA-binding motif. DNA microarray analysis of an E. coli puuR muta...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00097-12
更新日期:2012-07-01 00:00:00
abstract::In this study, we show that Salmonella produces an O-antigen capsule coregulated with the fimbria- and cellulose-associated extracellular matrix. Structural analysis of purified Salmonella extracellular polysaccharides yielded predominantly a repeating oligosaccharide unit similar to that of Salmonella enterica serova...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00809-06
更新日期:2006-11-01 00:00:00
abstract::The csgA gene produces an intercellular signal during fruiting body formation of the myxobacterium Myxococcus xanthus. Sporulating pseudorevertants were isolated to allow us to understand the mechanism by which CsgA is perceived by cells and used to regulate developmental gene expression. Two strains, LS559 and LS560,...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.176.8.2200-2209.1994
更新日期:1994-04-01 00:00:00
abstract::The major sheath protein-encoding gene (mspA) of the oral spirochete Treponema maltophilum ATCC 51939(T) was cloned by screening a genomic library with an anti-outer membrane fraction antibody. The mspA gene encodes a precursor protein of 575 amino acids with a predicted molecular mass of 62.3 kDa, including a signal ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.181.3.1025-1029.1999
更新日期:1999-02-01 00:00:00
abstract::Acetate kinase catalyzes the reversible phosphorylation of acetate (CH3COO- + ATP<-->CH3CO2PO3(2-) + ADP). A mechanism which involves a covalent phosphoryl-enzyme intermediate has been proposed, and chemical modification studies of the enzyme from Escherichia coli indicate an unspecified glutamate residue is phosphory...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.180.5.1129-1134.1998
更新日期:1998-03-01 00:00:00
abstract::MobB is a small protein encoded by the broad-host-range plasmid R1162 and required for efficient mobilization of its DNA during conjugation. The protein was shown previously to stabilize the relaxosome, the complex of plasmid DNA and mobilization proteins at the origin of transfer (oriT). We have generated in-frame mo...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.181.7.2124-2131.1999
更新日期:1999-04-01 00:00:00
abstract::Soluble reduced nicotinamide adenine dinucleotide oxidase activity in extracts of Bacillus subtilis spores was stimulated by the addition of not only flavine mononucleotide (FMN) or flavine adenine dinucleotide (FAD) but also alpha-alpha'-dipyridyl or o-phenanthroline. These chelating agents showed stronger effect on ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.117.3.1017-1022.1974
更新日期:1974-03-01 00:00:00
abstract::FtsK is essential for Escherichia coli cell division. We report that cells lacking the C terminus of FtsK are defective in chromosome segregation as well as septation, often exhibiting asymmetrically positioned nucleoids and large anucleate regions. Combining the corresponding truncated ftsK gene with a mukB null muta...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:
更新日期:1998-12-01 00:00:00
abstract::During bacteriophage T7 infection, the Escherichia coli RNA polymerase beta' subunit is phosphorylated by the phage-encoded kinase Gp0.7. Here, we used proteolytic degradation and mutational analysis to localize the phosphorylation site to a single amino acid, Thr(1068), in the evolutionarily hypervariable segment of ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.188.10.3470-3476.2006
更新日期:2006-05-01 00:00:00
abstract::Polyamines are present in high concentrations in archaea, yet little is known about their synthesis, except by extrapolation from bacterial and eucaryal systems. S-Adenosylmethionine (AdoMet) decarboxylase, a pyruvoyl group-containing enzyme that is required for spermidine biosynthesis, has been previously identified ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.182.23.6667-6672.2000
更新日期:2000-12-01 00:00:00
abstract::Catabolic mannopine (MOP) cyclase encoded by certain Agrobacterium Ti and Ri plasmids lactonizes MOP to agropine (AGR). The enzyme, purified to homogeneity from a recombinant clone, has a molecular mass of 45 kDa as measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and size exclusion chromatography...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.178.8.2427-2430.1996
更新日期:1996-04-01 00:00:00
abstract::Halobacterium halobium spontaneously reverses its swimming direction with a frequency of about 0.1 s-1. The self-sustained periodicity can be entrained by rhythmic light stimuli within a limited range between 0.13 and 0.3 s-1. Increase of temperature increases the reversal frequency and shortens the time to reach maxi...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.166.2.689-692.1986
更新日期:1986-05-01 00:00:00
abstract::The intermolecular interactions of the mycobacteriophage Ms6 secretion chaperone with endolysin were characterized. The 384-amino-acid lysin (lysin(384))-binding domain was found to encompass the N-terminal region of Gp1, which is also essential for a lysis phenotype in Escherichia coli. In addition, a GXXXG-like moti...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00380-11
更新日期:2011-09-01 00:00:00
abstract::The growth phase-dependent change in sucrose density gradient centrifugation patterns of ribosomes was analyzed for both laboratory strains of Escherichia coli and natural isolates from the ECOR collection. All of the natural isolates examined formed 100S ribosome dimers in the stationary phase, and ribosome modulatio...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.182.10.2893-2899.2000
更新日期:2000-05-01 00:00:00
abstract::Transposon Tn5-induced C4-dicarboxylate transport mutants of Rhizobium meliloti 2011 which could be complemented by cosmid pRmSC121 were subdivided into two classes. Class I mutants (RMS37 and RMS938) were defective in symbiotic C4-dicarboxylate transport and in nitrogen fixation. They were mutated in the structural g...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.171.10.5551-5560.1989
更新日期:1989-10-01 00:00:00
abstract::The regulatory proteins OmpR and EnvZ are both required to activate expression of the genes for the major outer membrane porin proteins, OmpF and OmpC, of Escherichia coli K-12. Here we show that OmpR, under certain conditions, could activate porin expression in the complete absence of EnvZ. In addition, the pleiotrop...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.170.1.439-441.1988
更新日期:1988-01-01 00:00:00
abstract::A plasmid, R773, which confers resistance to arsenic compounds, is transmissible between strains of Escherichia coli. It is a member of compatibility group F(1). ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.115.1.459-460.1973
更新日期:1973-07-01 00:00:00
abstract::Among 30 conjugative plasmids of enteric bacteria from 23 incompatibility (Inc) groups, we found 19 (from 12 Inc groups) which can complement defects caused by a defective single-stranded DNA-binding protein of Escherichia coli K-12. The genes which are responsible for the complementation from three of these plasmids ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.162.1.235-241.1985
更新日期:1985-04-01 00:00:00
abstract::Romano, Antonio H. (University of Cincinnati, Cincinnati, Ohio), and Dorothy J. Geason. Pattern of sheath synthesis in Sphaerotilus natans. J. Bacteriol. 88:1145-1150. 1964.-Formation of the characteristic sheath of Sphaerotilus natans was followed by immunofluorescence. Fluorescent antisheath antibody was obtained by...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.88.4.1145-1150.1964
更新日期:1964-10-01 00:00:00
abstract::To isolate genes from Escherichia coli which regulate the labile hydrogenase activity, a plasmid library was used to transform hydL mutants lacking the labile hydrogenase. A single type of gene, designated hydG, was isolated. This gene also partially restored the hydrogenase activity in hydF mutants (which are defecti...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.171.8.4448-4456.1989
更新日期:1989-08-01 00:00:00
abstract::The halophilic bacterium Chromohalobacter salexigens synthesizes and accumulates compatible solutes in response to salt and temperature stress. (13)C-nuclear magnetic resonance analysis of cells grown in minimal medium at the limiting temperature of 45 degrees C revealed the presence of hydroxyectoine, ectoine, glutam...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00136-06
更新日期:2006-06-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.184.3.859-860.2002
更新日期:2002-02-01 00:00:00
abstract::The trfA gene of the broad-host-range plasmid RK2 is essential for initiation of plasmid replication. Two related TrfA proteins of 43 and 32 kilodaltons (kDa) are produced by independent translation initiation at two start codons within the trfA open reading frame. These proteins were o overproduced in Escherichia col...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.172.7.3849-3858.1990
更新日期:1990-07-01 00:00:00
abstract::A procedure is presented for the rapid screening of bacterial colonies to detect mutants unable to produce 14CO2 from a labeled precursor. The method is especially useful for mass screening for mutants that cannot be easily detected by their phenotypic characteristics. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.128.1.485-486.1976
更新日期:1976-10-01 00:00:00