Abstract:
:The effects of the free bile acids (FBAs) cholic acid (CA), deoxycholic acid (DCA), and chenodeoxycholic acid on the bioenergetics and growth of lactobacilli and bifidobacteria were investigated. It was found that these FBAs reduced the internal pH levels of these bacteria with rapid and stepwise kinetics and, at certain concentrations, dissipated DeltapH. The bile acid concentrations that dissipated DeltapH corresponded with the MICs for the selected bacteria. Unlike acetate, propionate, and butyrate, FBAs dissipated the transmembrane electrical potential (DeltaPsi). In Bifidobacterium breve JCM 1192, the synthetic proton conductor pentachlorophenol (PCP) dissipated DeltapH with a slow and continuous kinetics at a much lower concentration than FBAs did, suggesting the difference in mode of action between FBAs and true proton conductors. Membrane damage assessed by the fluorescence method and a viability decrease were also observed upon exposure to CA or DCA at the MIC but not to PCP or a short-chain fatty acid mixture. Loss of potassium ion was observed at CA concentrations more than 2 mM (0.4x MIC), while leakage of other cellular components increased at CA concentrations more than 4 mM (0.8 x MIC). Additionally, in experiments with membrane phospholipid vesicles extracted from Lactobacillus salivarius subsp. salicinius JCM 1044, CA and DCA at the MIC collapsed the DeltapH with concomitant leakage of intravesicular fluorescent pH probe, while they did not show proton conductance at a lower concentration range (e.g., 0.2x MIC). Taking these observations together, we conclude that FBAs at the MIC disturb membrane integrity and that this effect can lead to leakage of proton (membrane DeltapH and DeltaPsi dissipation), potassium ion, and other cellular components and eventually cell death.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Kurdi P,Kawanishi K,Mizutani K,Yokota Adoi
10.1128/JB.188.5.1979-1986.2006keywords:
subject
Has Abstractpub_date
2006-03-01 00:00:00pages
1979-86issue
5eissn
0021-9193issn
1098-5530pii
188/5/1979journal_volume
188pub_type
杂志文章abstract::Scanning electron microscopy was used to examine the major stages of the life cycle of two wild-type strains of Neurospora crassa Shear and Dodge (St. Lawrence 3.1a and 74A): mycelia, protoperithecium formation, perithecia, ascospores, ascospore germination and outgrowth, macro and microconidia, and germination and ou...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.113.2.1015-1025.1973
更新日期:1973-02-01 00:00:00
abstract::A mathematical analysis of branched pathway regulation has led to the prediction of a novel homoserine control in Escherichia coli B. Experimental support for such control is presented in this paper. Homoserine, the precursor of both threonine and methionine, inhibits nicotinamide adenine dinucleotide phosphate (NADP(...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.116.2.663-672.1973
更新日期:1973-11-01 00:00:00
abstract::Acid phosphatase V of Aspergillus nidulans was purified by ammonium sulfate precipitation, gel filtration, and ion-exchange chromatography. The enzyme demonstrated a charge microheterogeneity on starch and acrylamide gel electrophoresis, but proved to be homogeneous on ultracentrifugation and gel filtration. Phosphata...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.110.1.246-255.1972
更新日期:1972-04-01 00:00:00
abstract::Sequencing the insertion sites of 8,865 Tn917 insertions in Enterococcus faecalis strain OG1RF identified a hot spot in the replication terminus region corresponding to 6% of the genome where 65% of the transposons had inserted. In E. faecalis, Tn917 preferentially inserted at a 29-bp consensus sequence centered on TA...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.186.21.7280-7289.2004
更新日期:2004-11-01 00:00:00
abstract::The 2-(methylthio)ethanesulfonic acid (CH3-S-CoM) reductase catalyzes the final methane-yielding reaction in fastidiously anaerobic methanogenic archaebacteria. This step involves the reductive demethylation of CH3-S-CoM with reducing equivalents from N-7-(mercaptoheptanoyl)-L-threonine O3-phosphate (HS-HTP) to yield ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.174.3.1007-1012.1992
更新日期:1992-02-01 00:00:00
abstract::Two deoxyribonucleic acid (DNA)-dependent ribonucleic acid (RNA) polymerases (I, II) have been solubilized from isolated Saccharomyces cerevisiae nuclei. The enzymes can be separated by chromatography on O-diethylaminoethyl Sephadex. Both enzymes are active with high-molecular-weight nuclear yeast DNA, although RNA po...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.114.1.1-6.1973
更新日期:1973-04-01 00:00:00
abstract::MinD binds to phospholipid vesicles in the presence of ATP and is released by MinE, which stimulates the MinD ATPase. Membrane binding requires a short conserved C-terminal region, which has the potential to form an amphipathic helix. This finding has led to a model in which the binding of ATP regulates the formation ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.185.15.4326-4335.2003
更新日期:2003-08-01 00:00:00
abstract::In response to molecular oxygen and/or fixed nitrogen, the product of the Klebsiella pneumoniae nitrogen fixation L (nifL) gene inhibits NifA-mediated transcriptional activation. Nitrogen regulation of NifL function occurs at two levels: transcription of the nifLA operon is regulated by the general Ntr system, and the...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.179.23.7446-7455.1997
更新日期:1997-12-01 00:00:00
abstract::Transposon mutagenesis was used to isolate mutants of Aeromonas hydrophila which were deficient in the production of extracellular proteins. The culture supernatants of two of the mutants were essentially devoid of the proteins normally secreted by the parent strain, despite their continued synthesis. Western immunobl...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.173.3.1241-1249.1991
更新日期:1991-02-01 00:00:00
abstract::Phospholipid synthesis has been reported to be subject to stringent control in Escherichia coli. We present evidence that demonstrates a strict correlation between guanosine tetraphosphate accumulation and inhibition of phospholipid synthesis. In vivo experiments designed to examine the pattern of phospholipid labelin...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.116.1.355-366.1973
更新日期:1973-10-01 00:00:00
abstract::Pseudomonas sp. strain LB400 grows on biphenyl as the sole carbon and energy source. This organism also cooxidizes several chlorinated biphenyl congeners. Biphenyl dioxygenase activity in cell extract required addition of NAD(P)H as an electron donor for the conversion of biphenyl to cis-2,3-dihydroxy-2,3-dihydrobiphe...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.2.395-400.1993
更新日期:1993-01-01 00:00:00
abstract::The gene encoding OprF, a major outer membrane protein in Pseudomonas species (formerly known as type 1 pseudomonads), was thought to be constitutively transcribed from a single sigma 70 promoter immediately upstream of the gene. We now report the identification of a novel putative ECF (extracytoplasmic function) sigm...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.181.16.4746-4754.1999
更新日期:1999-08-01 00:00:00
abstract::In gram-negative organisms, enzymes belonging to the low-molecular-weight protein tyrosine phosphatase (LMPTP) family are involved in the regulation of important physiological functions, including stress resistance and synthesis of the polysaccharide capsule. LMPTPs have been identified also in gram-positive bacteria,...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.187.14.4945-4956.2005
更新日期:2005-07-01 00:00:00
abstract::DNA damage and perturbations in DNA replication can induce global transcriptional responses that can help organisms repair the damage and survive. RecA is known to mediate transcriptional responses to DNA damage in several bacterial species by inactivating the repressor LexA and phage repressors. To gain insight into ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00342-06
更新日期:2006-08-01 00:00:00
abstract::In all organisms, chromosome replication is regulated mainly at the initiation step. Most of the knowledge about the mechanisms that regulate replication initiation in bacteria has come from studies on rod-shaped bacteria, such as Escherichia coli and Bacillus subtilisStreptomyces is a bacterial genus that is characte...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00597-19
更新日期:2020-01-15 00:00:00
abstract::The vir locus of Bordetella pertussis apparently encodes a trans-acting positive regulator that is required for the coordinate expression of genes associated with virulence: pertussis toxin, filamentous hemagglutinin (FHA), hemolysin, and adenylate cyclase toxin. DNA clones of vir and of genes required for the synthes...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.170.7.2904-2913.1988
更新日期:1988-07-01 00:00:00
abstract::A modified 3-hydroxypropionate cycle has been proposed as the autotrophic CO2 fixation pathway for the thermoacidophilic crenarchaeon Metallosphaera sedula. The cycle requires the reductive conversion of 3-hydroxypropionate to propionyl-coenzyme A (propionyl-CoA). The specific activity of the 3-hydroxypropionate-, CoA...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01593-07
更新日期:2008-02-01 00:00:00
abstract::In Escherichia coli the SOS response, induced by DNA-damaging treatments, includes two systems of cell division inhibition, SfiA and SfiC, which are thought to prevent cell division by interacting with the division protein FtsZ. It is shown here that SfiA-mediated division inhibition is readily reversible, even in the...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.166.3.733-738.1986
更新日期:1986-06-01 00:00:00
abstract::Fitz-James, Philip (University of Western Ontario, London, Canada). Electron microscopy of Bacillus megaterium undergoing isolation of its nucelar bodies. J. Bacteriol. 87:1202-1210. 1964.-The various steps of treatment leading to the isolation of nuclear bodies were followed by thin-section electron microscopy. Nucle...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.87.5.1202-1210.1964
更新日期:1964-05-01 00:00:00
abstract::To elucidate the biological functions of the ribosomal protein L34, which is encoded by the rpmH gene, the rpmH deletion mutant of Bacillus subtilis and two suppressor mutants were characterized. Although the ΔrpmH mutant exhibited a severe slow-growth phenotype, additional mutations in the yhdP or mgtE gene restored ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01896-14
更新日期:2014-11-01 00:00:00
abstract::Polysaccharide-containing material was located by histochemical staining on ultrathin sections of Bacillus cereus and several clostridial species during various phases of growth. These components were located along the cell wall in young vegetative cells and along the developing cortex in sporulating cells. In B. cere...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.98.3.1342-1354.1969
更新日期:1969-06-01 00:00:00
abstract::Methicillin resistance in staphylococci is mediated by PBP2a, a penicillin binding protein with low affinity for beta-lactam antibiotics. The gene encoding PBP2a, mecA, is transcriptionally regulated in some clinical isolates by mecR1 and mecI, genes divergently transcribed from mecA that encode a signal transducer an...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.180.8.2160-2166.1998
更新日期:1998-04-01 00:00:00
abstract::We report the draft genome of the strain Lactobacillus gigeriorum CRBIP 24.85(T), isolated from a chicken crop. The total length of the 60 scaffolds is about 1.9 Mb, with a GC content of 38% and 2,062 protein-coding sequences (CDS). ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.01427-12
更新日期:2012-11-01 00:00:00
abstract::We have identified and characterized enzymes of phospholipid synthesis in two plasmalogen-rich anaerobes. Megasphaera elsdenii and Veillonella parvula, and one anaerobe lacking plasmalogens. Desulfovibrio vulgaris. All three species contained phosphatidate cytidylyltransferase and phosphatidylserine synthase. Phosphat...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.147.1.57-61.1981
更新日期:1981-07-01 00:00:00
abstract::After thermal denaturation, an in vivo-labeled RNA was found in a temperature-sensitive initiation mutant of Bacillus subtilis (dna-37) associated with high-molecular-weight DNA. This RNA could be clearly distinguished from other RNA species by different techniques of separation, such as Sepharose 2B filtration, chrom...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.149.1.79-91.1982
更新日期:1982-01-01 00:00:00
abstract::A homologue of the grmA spore germination gene of Bacillus megaterium and of a NaH-antiporter gene (napA) of Enterococcus hirae has been identified in Bacillus cereus 569 (ATCC 10876). The putative protein product has 58 and 43% amino acid identity with GrmA and NapA, respectively. Insertional inactivation of this B. ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.183.2.476-482.2001
更新日期:2001-01-01 00:00:00
abstract::The lytD1 mutant of Escherichia coli exhibits temperature-sensitive growth which is attributed to cellular autolysis at the restrictive temperature. Either of two cloned phage lambda genes, identified as cI and cro, suppressed the lytD1(Ts) lysis phenotype, suggesting that lytD encodes a DNA-binding protein with a DNA...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.173.2.893-895.1991
更新日期:1991-01-01 00:00:00
abstract::The recF gene of Escherichia coli is known to encode an Mr-40,000 protein that is involved in DNA recombinationa nd postreplication DNA repair. To characterize the role of the recF gene product in these processes, the recF gene was cloned downstream of a tac promoter to facilitate overproduction of the recF gene produ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.172.11.6291-6299.1990
更新日期:1990-11-01 00:00:00
abstract::Heterocyst differentiation is orchestrated by the N control transcriptional regulator NtcA and the differentiation-specific factor HetR. In Anabaena sp. strain PCC 7120, the devBCA operon is expressed from two different promoters activated upon N stepdown. The distal devB promoter (transcription start point [TSP] loca...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.05994-11
更新日期:2012-06-01 00:00:00
abstract::We characterized the traU gene of the Escherichia coli K-12 conjugative plasmid F. Plasmids carrying segments of the F transfer operon were tested for their capacity to complement F lac traU526. The protein products of TraU+ clones were identified, and the nucleotide sequence of traU was determined. traU mapped betwee...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.172.8.4263-4270.1990
更新日期:1990-08-01 00:00:00