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 polymerase chain reaction (PCR) has been used to amplify DNA fragments by using eucaryotic genomic DNA as a template. We show that bacterial genomic DNA can be used as a template for PCR amplification. We demonstrate that DNA fragments at least as large as 4,400 base pairs can be amplified with fidelity and that t...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.171.3.1602-1608.1989
更新日期:1989-03-01 00:00:00
abstract::Neisseria gonorrhoeae is prone to undergo autolysis under many conditions not conducive to growth. The role of autolysis during gonococcal infection is not known, but possible advantages for the bacterial population include provision of nutrients to a starving population, modulation of the host immune response by rele...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00724-06
更新日期:2006-10-01 00:00:00
abstract::Escherichia coli AT2046 has been shown previously to lack the enzyme serine transhydroxymethylase and to require exogenous glycine for growth as a consequence. Strains JEV73 and JEV73R, mutants derived from strain AT2046, are shown here to be serine transhydroxymethylase deficient, but able to derive their glycine fro...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.122.3.810-817.1975
更新日期:1975-06-01 00:00:00
abstract::The obligate intracellular pathogen Chlamydia trachomatis expresses a type III secretion system (T3SS) which has the potential to contribute significantly to pathogenesis. Based on a demonstrated role of type III secretion (T3S)-specific chaperones in the secretion of antihost proteins by gram-negative pathogens, we i...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.187.18.6466-6478.2005
更新日期:2005-09-01 00:00:00
abstract::The location of the Escherichia coli K-12 genes determining or regulating glutamate transport, and the location of the gene determining glutamate decarboxylase synthesis, were established by conjugation. The ability to grow on glutamate as the sole source of carbon and energy was used to select for glutamate transport...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.93.4.1409-1415.1967
更新日期:1967-04-01 00:00:00
abstract::Whether or not bacteria form coherent evolutionary groups via means of genetic exchange and, hence, elicit distinct species boundaries remains an unsettled issue. A recent report implied that not only may the former be true but also, in fact, the clearly distinct Campylobacter jejuni and Campylobacter coli species may...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00519-09
更新日期:2009-09-01 00:00:00
abstract::The three-component naphthalene dioxygenase (NDO) enzyme system carries out the first step in the aerobic degradation of naphthalene by Pseudomonas sp. strain NCIB 9816-4. The three-dimensional structure of NDO revealed that several of the amino acids at the active site of the oxygenase are hydrophobic, which is consi...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.182.6.1641-1649.2000
更新日期:2000-03-01 00:00:00
abstract::Until the question of symmetry or asymmetry in the facilitated diffusion of monosaccharides by Saccharomyces cerevisiae is resolved, attempts to study the transport process cannot be based on assumptions of symmetry, such as equal concentrations at equilibrium or kinetic parameters that are equal in opposite direction...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.113.2.612-618.1973
更新日期:1973-02-01 00:00:00
abstract::The halophilic bacterium Halomonas elongata synthesizes as its main compatible solute the aspartate derivative ectoine. We constructed a deletion mutant of H. elongata, KB1, defective in ectoine synthesis and tolerating elevated salt concentrations only in the presence of external compatible solutes. The dependency of...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.184.11.3078-3085.2002
更新日期:2002-06-01 00:00:00
abstract::When incubated in the light under 100% oxygen, wild-type blue-green algae (Anacystis nidulans, Synechococcus cedrorum) die out rapidly at temperatures of 4 to 15 C, and at 35 C (or at 26 C in the case of S. cedrorum) in the absence of CO(2). Photosynthesis is impaired in these cells long before they die. Blocking of p...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.111.3.682-689.1972
更新日期:1972-09-01 00:00:00
abstract::A widely distributed family of small regulators, called C proteins, controls a subset of restriction-modification systems. The C proteins studied to date activate transcription of their own genes and that of downstream endonuclease genes; this arrangement appears to delay endonuclease expression relative to that of th...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.187.2.488-497.2005
更新日期:2005-01-01 00:00:00
abstract::The structures of the lipooligosaccharides (LOSs) from Haemophilus ducreyi ITM 5535 and ITM 3147 and a fresh clinical isolate, ACY1, have been investigated. Oligosaccharides were obtained from phenol-water-extracted LOS by mild acid hydrolysis and were studied by methylation analysis, fast atom bombardment and electro...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.177.18.5316-5321.1995
更新日期:1995-09-01 00:00:00
abstract::A phage-induced cell wall solubilizing enzyme isolated from phage-infected Staphylococcus aureus phage type 80 was purified 588-fold. The pH optimal activity was 6.8 to 7.3, and pH optimal stability, 6.5 to 7.5. It was inhibited by p-hydroxymercuribenzoate, ethylenediaminetetraacetic acid, and specific rabbit antisera...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.93.3.1089-1095.1967
更新日期:1967-03-01 00:00:00
abstract::The function of the essential inner membrane protein (IMP) YidC in Escherichia coli has been studied for a limited number of model IMPs and primarily using targeted approaches. These studies suggested that YidC acts at the level of insertion, folding, and quality control of IMPs, both in the context of the Sec translo...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01209-10
更新日期:2011-03-01 00:00:00
abstract::Oxalate catabolism is conducted by phylogenetically diverse organisms, including Methylobacterium extorquens AM1. Here, we investigate the central metabolism of this alphaproteobacterium during growth on oxalate by using proteomics, mutant characterization, and (13)C-labeling experiments. Our results confirm that ener...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00288-12
更新日期:2012-06-01 00:00:00
abstract::Heat, salinity, or osmotic stress influenced protein synthesis in nitrogen-fixing Anabaena sp. strain L-31. Salinity and osmotic stresses were identical and specifically induced 15 polypeptides. Four polypeptides were unique to heat shock, and four other polypeptides were induced under every stress. The results demons...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.171.9.5187-5189.1989
更新日期:1989-09-01 00:00:00
abstract::Pleiotropic effects of two ribosomal mutations for cycloheximide resistance were studied in a double-resistant homocaryon. The results obtained indicated that the combination of the two ribosomal mutations results in: (i) morphological abnormalities which suggest a severe distortion in the extension of cell walls and ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.139.2.620-624.1979
更新日期:1979-08-01 00:00:00
abstract::We describe here the cloning of single EcoRI fragments from the tra region of F DNA using ColE1::Tn3 as vector. These plasmids, as well as the series of Skurray et al. (Proc. Natl. Acad. Sci. U.S.A. 73:64-68, 1976), have been used to refine the map positions of tra cistrons on the F factor as well as to define a new D...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.133.3.1383-1392.1978
更新日期:1978-03-01 00:00:00
abstract::We have isolated three strains of Klebsiella aerogenes that failed to show repression of glutamine synthetase even when grown under the most repressing conditions for the wild-type strain. These mutant strains were selected as glutamine-independent derivatives of a strain that is merodiploid for the glnA region and co...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.141.2.671-679.1980
更新日期:1980-02-01 00:00:00
abstract::The nucleotide sequence of the DNA mobilization region of the 5-nitroimidazole resistance plasmid pIP421, from strain BF-F239 of Bacteroides fragilis, was determined. It contains a putative origin of transfer (oriT) including three sets of inverted repeats and two sequences reminiscent of specific integration host fac...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.179.12.4071-4074.1997
更新日期:1997-06-01 00:00:00
abstract::The anti-inflammatory drug phenylbutazone has been found to inhibit both engulfment and intracellular killing of E. coli by guinea pig peritoneal polymorphonuclear (PMN) leukocytes. The bactericidal activity of leukocytic homogenates was also inhibited by the drug. Addition of the drug at various time intervals to a p...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.96.6.1982-1990.1968
更新日期:1968-12-01 00:00:00
abstract::Nishida, S. (Kanazawa University, Kanazawa, Japan), and G. Nakagawara. Isolation of toxigenic strains of Clostridium novyi from soil. J. Bacteriol. 88:1636-1640. 1964.-The cultural conditions for toxin production by Clostridium novyi were investigated, and the optimal constituents of a proper medium were determined. A...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.88.6.1636-1640.1964
更新日期:1964-12-01 00:00:00
abstract::The diphtheria toxin repressor (DtxR) of Corynebacterium diphtheriae uses Fe(2+) as a corepressor. Holo-DtxR inhibits transcription from the iron-regulated promoters (IRPs) designated IRP1 through IRP5 as well as from the promoters for the tox and hmuO genes. DtxR binds to 19-bp operators with the consensus sequence 5...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.182.2.432-438.2000
更新日期:2000-01-01 00:00:00
abstract::The ftsB gene of Escherichia coli is believed to be involved in cell division. In this report, we show that plasmids containing the nrdB gene could complement the ftsB mutation, suggesting that ftsB is an allele of nrdB. We compared changes in the cell shape of isogenic nrdA, nrdB, ftsB, and pbpB strains at permissive...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.169.1.19-25.1987
更新日期:1987-01-01 00:00:00
abstract::The expression of Escherichia coli purR, which encodes the pur regulon repressor protein, is autoregulated. Autoregulation at the level of transcription requires two operator sites, designated purRo1 and purRo2 (O1 and O2). Operator O1 is in the region of DNA between the transcription start site and the site for trans...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.172.10.5758-5766.1990
更新日期:1990-10-01 00:00:00
abstract::Incubation of whole envelopes prepared from sonically oscillated Escherichia coli K-12 cultures with lysozyme in vitro resulted in the appearance of a protein species with an apparent molecular weight double that of outer membrane protein I. Similar dimers were also detected in purified outer membranes and whole envel...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.132.2.411-418.1977
更新日期:1977-11-01 00:00:00
abstract::The kinetics of chromosome replication and cell division have been examined in recA mutants of Escherichia coli B/r containing F' plasmids of various sizes. Plasmid-mediated alterations in growth properties were detected only with the presence of the larger F' plasmids, and were reflected in decreased mean cell sizes ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.137.3.1151-1157.1979
更新日期:1979-03-01 00:00:00
abstract::The mechanisms by which hyperthermophilic Archaea, such as "Pyrococcus abyssi" and Pyrococcus furiosus, survive high doses of ionizing gamma irradiation are not thoroughly elucidated. Following gamma-ray irradiation at 2,500 Gy, the restoration of "P. abyssi" chromosomes took place within chromosome fragmentation. DNA...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.185.13.3958-3961.2003
更新日期:2003-07-01 00:00:00
abstract::Sinorhizobium meliloti strains lacking BacA function are impaired in symbiosis with alfalfa host plants and display altered sensitivities to a number of compounds relative to wild-type strains. With the goal of finding clues to the currently unknown biological function(s) of BacA, we carried out a genetic analysis to ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.183.21.6444-6453.2001
更新日期:2001-11-01 00:00:00
abstract::Integration host factor (IHF) is a small, basic protein that is needed for efficient recombination of bacteriophage lambda, as well as for other host and viral functions. We have constructed strains in which the two subunits of IHF, encoded by the himA and hip genes of Escherichia coli, are expressed under the control...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.169.9.4124-4127.1987
更新日期:1987-09-01 00:00:00