Abstract:
:Helicobacter pylori genomes contain about 30 hop genes that encode outer membrane proteins. Helicobacter pylori hopQ alleles exhibit a high level of genetic diversity, and two families of hopQ alleles have been described. Type I hopQ alleles are found more commonly in cag-positive H. pylori strains from patients with peptic ulcer disease than in cag-negative strains from patients without ulcer disease. In this study, we mutated hopQ in four H. pylori strains that each contained a type I hopQ allele, and then analyzed interactions of the wild-type and hopQ mutant strains with AGS cells. In comparison with the wild-type strains, two of the hopQ mutant strains exhibited increased adherence to AGS cells and two hopQ mutants did not exhibit any detectable differences in adherence. Higher levels of tyrosine-phosphorylated CagA were detected when AGS cells were cocultured with a hyperadherent hopQ mutant strain than when cocultured with the corresponding wild-type strain. These data indicate that in some strains of H. pylori, the HopQ protein can attenuate bacterial adherence to gastric epithelial cells.
journal_name
FEMS Microbiol Lettjournal_title
FEMS microbiology lettersauthors
Loh JT,Torres VJ,Algood HM,McClain MS,Cover TLdoi
10.1111/j.1574-6968.2008.01368.xsubject
Has Abstractpub_date
2008-12-01 00:00:00pages
53-8issue
1eissn
0378-1097issn
1574-6968journal_volume
289pub_type
杂志文章abstract::Nocardioides sp. strain MTD22 degraded atrazine, ametryn and atraton, as did Arthrobacter aurescens strain TC1 and Nocardioides sp. strain C190. These strains contain trzN, a gene coding for TrzN, triazine hydrolase showing a broad substrate range. However, Nocardioides sp. strain AN3 degraded only atrazine despite co...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2008.01271.x
更新日期:2008-09-01 00:00:00
abstract::Brief exposure of Pseudomonas aeruginosa to a temperature of 10 degrees C or lower caused a significant leakage of the periplasmic beta-lactamase into the medium. The extent of leakage increased as the incubation temperature was lowered to 4 degrees C and reached a maximum at 0 degrees C. Cells grown in the presence o...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/0378-1097(91)90620-p
更新日期:1991-05-15 00:00:00
abstract::The high-pathogenicity island (Yen HPI) of Yersinia enterocolitica biogroup (BG) 1B strains is associated with mouse virulence. Three repeated sequences are clustered on the A+T-rich part of the Yen HPI downstream of the fyuA yersiniabactin receptor gene in Y. enterocolitica O:8 strains WA-314 and 8081. In addition to...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2000.tb08899.x
更新日期:2000-01-15 00:00:00
abstract::As shown by both bioassay and high-performance liquid chromatographic (HPLC) analysis, penicillin G production by Aspergillus nidulans is subject to regulation by the pH of the growth medium. Penicillin titres were highest at alkaline pH and in strains carrying mutations in the regulatory gene pacC which mimics the ef...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/0378-1097(91)90553-m
更新日期:1991-01-15 00:00:00
abstract::Hopanoid fingerprints allowed to differentiate bacteria formerly connected to the genus Pseudomonas. Whereas all strains related to Pseudomonas and Ralstonia were devoid of any detectable hopanoid, these pentacyclic triterpenoids were found in the Burkholderia species and in related soil isolates, which contained as m...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2000.tb08974.x
更新日期:2000-02-15 00:00:00
abstract::The effects of oxidoreduction potential (Eh) combined with acetic acid, NaCl and temperature on the growth, acidification, and membrane properties of Lactobacillus plantarum were studied. The culture medium was set at pH 5, and two different Eh values were adjusted using nitrogen (Eh = +350 mV) or hydrogen (Eh = -300 ...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2002.tb11356.x
更新日期:2002-09-10 00:00:00
abstract::The devR-devS two-component system of Mycobacterium tuberculosis was identified earlier and partially characterized in our laboratory. A devR::kan mutant of M. tuberculosis was constructed by allelic exchange. The devR mutant strain showed reduced cell-to-cell adherence in comparison to the parental strain in laborato...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/S0378-1097(04)00002-3
更新日期:2004-02-16 00:00:00
abstract::The scrA gene coding for sucrose EnzymeII of the phosphoenolpyruvate dependent phosphotransferase system previously isolated from Streptococcus mutans was fused in vitro to the promoterless lacZ' gene to monitor the expression of the scrA gene. The scrA::lacZ gene fusion was introduced back into S. mutans GS-5IS3 by t...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.1991.tb04552.x
更新日期:1991-04-15 00:00:00
abstract::The study compared images of mature Streptococcus mutans biofilms captured at increasing magnification to determine which microscopy method is most acceptable for imaging the biofilm topography and the extracellular polymeric substance (EPS). In vitro S. mutans biofilms were imaged using (1) scanning electron microsco...
journal_title:FEMS microbiology letters
pub_type: 信件
doi:10.1111/1574-6968.12334
更新日期:2014-01-01 00:00:00
abstract::A novel aerobic, Gram-negative bacterial strain, designated KU41E(T), which degrades p-n-nonylphenol, was isolated from seawater obtained from the coastal region of Ishigaki Island, Japan. Cells are motile, curved rods with a single polar flagellum. Strain KU41E(T) grew at 20-35 °C, pH 7.0-8.0, in the presence of 1.0-...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2011.02471.x
更新日期:2012-02-01 00:00:00
abstract::The malate dehydrogenase (MDH; EC 1.1.1.37; L-malate-NAD(+)-oxidoreductase) activities of truffles of the genus Tuber (Tuber melanosporum Vittad., Tuber brumale Vittad., Tuber aestivum Vittad., Tuber magnatum Pico, Tuber rufum Pico) have been characterized with regard to the K(m) and V(max) values in the direct and re...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2000.tb09064.x
更新日期:2000-04-15 00:00:00
abstract::This study investigated the impacts of bacterial DNA extraction methodology on downstream analysis of fish gut microbiota. Feces and intestine samples were taken from three sympatric freshwater fish species with varying diets. Samples were processed immediately (approximately 4 h after capture; fresh), stored at -20 °...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1093/femsle/fnu031
更新日期:2015-03-01 00:00:00
abstract::Listeria monocytogenes prfA, encoding positive regulatory factor A, is transcribed from three promoters (prfAP1, prfAP2, and PplcA). The prfAP2 promoter was previously proposed to be sigma B (sigma(B))-dependent. This hypothesis was tested by creating prfA promoter-gus transcriptional fusions in both L. monocytogenes ...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/j.femsle.2005.03.025
更新日期:2005-04-15 00:00:00
abstract::Multidrug resistance plasmids carrying the bla(CMY-2) gene have been identified in Salmonella enterica serovars Typhimurium and Newport from the United States. This gene confers decreased susceptibility to ceftriaxone, and is most often found in strains with concomitant resistance to ampicillin, chloramphenicol, strep...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/j.femsle.2004.02.023
更新日期:2004-04-15 00:00:00
abstract::Bacillus cereus is becoming one of the more important causes of food poisoning in the industrialised world. It produces one emetic toxin and three different enterotoxins. The emetic toxin is a ring-shaped structure of three repeats of four amino and/or oxy acids: [D-O-Leu-D-Ala-L-O-Val-L-Val]3. This ring structure has...
journal_title:FEMS microbiology letters
pub_type: 杂志文章,评审
doi:10.1111/j.1574-6968.1997.tb12776.x
更新日期:1997-12-15 00:00:00
abstract::Nine clinical isolates of Enterobacteriaceae (six Escherichia coli and three Proteus mirabilis) isolated in three Parisian hospitals between 1989 and 2000 showed a particular extended-spectrum cephalosporin-resistance profile characterized by resistance to cefotaxime and aztreonam but not to ceftazidime. CTX-M-1, CTX-...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2002.tb11126.x
更新日期:2002-04-09 00:00:00
abstract::The 181 251 bp accessory plasmid pSmeSM11b of Sinorhizobium meliloti strain SM11, belonging to a dominant indigenous S. meliloti subpopulation identified during a long-term field release experiment, was sequenced. This plasmid has 166 coding sequences (CDSs), 42% of which encode proteins with homology to proteins of k...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2007.00731.x
更新日期:2007-06-01 00:00:00
abstract::Within the phylum Bacteroidetes, the gyrB gene, encoding for the B subunit of the DNA gyrase, has been used as a phylogenetic marker for several genera closely related to Flavobacterium. The phylogenies of the complete 16S rRNA gene and the gyrB gene were compared for 33 Antarctic Flavobacterium isolates and 23 type s...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2011.02326.x
更新日期:2011-08-01 00:00:00
abstract::In the yearly Internationally Genetically Engineered Machines (iGEM) competition, teams of Bachelor's and Master's students design and build an engineered biological system using DNA technologies. Advising an iGEM team poses unique challenges due to the inherent difficulties of mounting and completing a new biological...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1093/femsle/fnw141
更新日期:2016-07-01 00:00:00
abstract::A strain of Agromyces fucosus, designated Vs2, metabolized a range of organophosphonate compounds as sole phosphorus sources for growth and metabolized phosphonoacetate as a sole carbon, energy and phosphorus source for growth. With phosphonoacetate as the sole phosphorus source and a pyruvate carbon source, transient...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2006.00344.x
更新日期:2006-08-01 00:00:00
abstract::Effects of the two-component sensor-regulator pairs DctBD and NtrBC upon the expression of a dctA::phoA fusion from Rhizobium meliloti were determined under excess and limiting nitrogen concentrations in Escherichia coli. Results indicated that NtrBC affected transcription from the dctA promoter on a number of regulat...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.1995.tb07531.x
更新日期:1995-05-15 00:00:00
abstract::Haloarchaea thrive under saline and hypersaline conditions and often dominate microbial communities in saltmarshes, salted lakes/soils and some oceanic areas. Some of the predominant species show denitrifying capabilities, although it remains unclear whether they are complete or partial denitrifiers. As complete denit...
journal_title:FEMS microbiology letters
pub_type: 杂志文章,评审
doi:10.1093/femsle/fnx270
更新日期:2018-02-01 00:00:00
abstract::To investigate the modular structure of the Rhizobium meliloti dicarboxylic acid sensor protein, DctB, three truncated DctB proteins (DctB4, DctB5 and DctB4G) were constructed, overproduced in Escherichia coli and purified. The DctB4G protein was composed of 446 amino acids of the DctB C-terminus and displayed strong ...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.1996.tb08174.x
更新日期:1996-05-15 00:00:00
abstract::The aim of this study was to screen two cheese starter cultures and cheese-borne microbial communities with the potential to produce biogenic amines in cheese during ripening. Bacteria of the genera Enterococcus and Lactobacillus and coliform bacteria were isolated from Dutch-type semi-hard cheese at the beginning of ...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1111/j.1574-6968.2007.00922.x
更新日期:2007-11-01 00:00:00
abstract::The flagellins of Methanospirillum hungatei strains JF1 and GP1, Methanococcus deltae, and Methanothermus fervidus are glycosylated. Isolated flagellar filaments from these organisms are dissociated by low concentrations (0.5% (v/v)) of Triton X-100. Flagellar filaments from other methanogens (Methanococcus voltae, Me...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/0378-1097(92)90616-v
更新日期:1992-01-01 00:00:00
abstract::In Taiwan, leptospirosis is caused mainly by Leptospira santarosai serovar shermani. Suppression subtractive hybridization was employed to isolate DNA fragments present in pathogenic L. santarosai serovar shermani but absent in non-pathogenic L. biflexa serovar patoc. Analysis of 23 subtracted DNA clones revealed 25 g...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/j.femsle.2004.04.024
更新日期:2004-06-01 00:00:00
abstract::In addition to core Cas proteins, CRISPR-Cas loci often encode ancillary proteins that modulate the activity of the respective effectors in interference. Subtype VI-B1 CRISPR-Cas systems encode the Csx27 protein that down-regulates the activity of Cas13b when the type VI-B locus is expressed in Escherichia coli. We sh...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1093/femsle/fnz088
更新日期:2019-04-01 00:00:00
abstract::We report for the first time the production of acyl homoserine lactones (AHLs) by Erwina amylovora, an important quarantine bacterial pathogen that causes fire blight in plants. E. amylovora produces one N-acyl homoserine lactone [a N-(3-oxo-hexanoyl)-homoserine lactone or a N-(3-hydroxy-hexanoyl)-homoserine lactone] ...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/j.femsle.2004.10.015
更新日期:2004-12-15 00:00:00
abstract::Biology education is undergoing a transformation toward a more student-centered, inquiry-driven classroom. Many educators have designed engaging assignments that are designed to help undergraduate students gain exposure to the scientific process and data analysis. One of these types of assignments is use of a grant pr...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1093/femsle/fnx024
更新日期:2017-02-01 00:00:00
abstract::An enzyme linked immune sorbent assay (ELISA) was developed to measure bacterial surface lipoteichoic acid (LTA). Numerous strains of oral streptococci belonging to the 'viridans' group were examined on three separate occasions. The results show that, under these cultural conditions, oral streptococci do not normally ...
journal_title:FEMS microbiology letters
pub_type: 杂志文章
doi:10.1016/0378-1097(89)90045-1
更新日期:1989-04-01 00:00:00