Abstract:
:Escherichia coli O157:H7 carried on plant surfaces, including alfalfa sprouts, has been implicated in food poisoning and outbreaks of disease in the United States. Adhesion to cell surfaces is a key component for bacterial establishment and colonization on many types of surfaces. Several E. coli O157:H7 surface proteins are thought to be important for adhesion and/or biofilm formation. Therefore, we examined whether mutations in several genes encoding potential adhesins and regulators of adherence have an effect on bacterial binding to plants and also examined the role of these genes during adhesion to Caco-2 cells and during biofilm formation on plastic in vitro. The genes tested included those encoding adhesins (cah, aidA1, and ompA) and mediators of hyperadherence (tdcA, yidE, waaI, and cadA) and those associated with fimbria formation (csgA, csgD, and lpfD2). The introduction of some of these genes (cah, aidA1, and csg loci) into an E. coli K-12 strain markedly increased its ability to bind to alfalfa sprouts and seed coats. The addition of more than one of these genes did not show an additive effect. In contrast, deletion of one or more of these genes in a strain of E. coli O157:H7 did not affect its ability to bind to alfalfa. Only the absence of the ompA gene had a significant effect on binding, and the plant-bacterium interaction was markedly reduced in a tdcA ompA double mutant. In contrast, the E. coli O157:H7 ompA and tdcA ompA mutant strains were only slightly affected in adhesion to Caco-2 cells and during biofilm formation. These findings suggest that some adhesins alone are sufficient to promote binding to alfalfa and that they may exist in E. coli O157:H7 as redundant systems, allowing it to compensate for the loss of one or more of these systems. Binding to the three types of surfaces appeared to be mediated by overlapping but distinct sets of genes. The only gene which appeared to be irreplaceable for binding to plant surfaces was ompA.
journal_name
Appl Environ Microbioljournal_title
Applied and environmental microbiologyauthors
Torres AG,Jeter C,Langley W,Matthysse AGdoi
10.1128/AEM.71.12.8008-8015.2005keywords:
subject
Has Abstractpub_date
2005-12-01 00:00:00pages
8008-15issue
12eissn
0099-2240issn
1098-5336pii
71/12/8008journal_volume
71pub_type
杂志文章abstract::A competitive enzyme-linked immunosorbent assay was used to screen for T-2 toxin in Fusarium sporotrichioides -infected corn. The assay detected T-2 toxin in diluted methanol extracts of corn samples at concentrations of 0.05 ng/ml. In infected corn samples, enzyme-linked immunosorbent assay and gas-liquid chromatogra...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.47.5.1161-1163.1984
更新日期:1984-05-01 00:00:00
abstract::Values of Delta(34)S (=delta(34)S(HS)-delta(34)S(SO(4)), where delta(34)S(HS) and delta(34)S(SO(4)) indicate the differences in the isotopic compositions of the HS(-) and SO(4)(2-) in the eluent, respectively) for many modern marine sediments are in the range of -55 to -75 per thousand, much greater than the -2 to -46...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02948-08
更新日期:2009-09-01 00:00:00
abstract::Laboratory-scale soil microcosms containing different soils were permeated with CH(inf4) for up to 6 months to investigate their capacity to develop a methanotrophic community. Methane emissions were monitored continuously until steady states were established. The porous, coarse sand soil developed the greatest methan...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.61.2.592-601.1995
更新日期:1995-02-01 00:00:00
abstract::Industrial production of the edible basidiomycete Pleurotus ostreatus (oyster mushroom) is based on a solid fermentation process in which a limited number of selected strains are used. Optimization of industrial mushroom production depends on improving the culture process and breeding new strains with higher yields an...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.69.6.3617-3625.2003
更新日期:2003-06-01 00:00:00
abstract::Shigella flexneri and Shigella sonnei bacteria cause the majority of all shigellosis cases worldwide. However, their distributions differ, with S. sonnei predominating in middle- and high-income countries and S. flexneri predominating in low-income countries. One proposed explanation for the continued range expansion ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02679-17
更新日期:2018-04-16 00:00:00
abstract::To study the impact of solar UV radiation (UVR) (280 to 400 nm) on the filamentous cyanobacterium Arthrospira (Spirulina) platensis, we examined the morphological changes and photosynthetic performance using an indoor-grown strain (which had not been exposed to sunlight for decades) and an outdoor-grown strain (which ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.71.9.5004-5013.2005
更新日期:2005-09-01 00:00:00
abstract::Two alpha-amylase genes from the thermophilic alkaliphile Anaerobranca gottschalkii were cloned, and the corresponding enzymes, AmyA and AmyB, were investigated after purification of the recombinant proteins. Based on their amino acid sequences, AmyA is proposed to be a lipoprotein with extracellular localization and ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.71.7.3709-3715.2005
更新日期:2005-07-01 00:00:00
abstract::We have analyzed the impact of surface-to-volume ratio on final bacterial concentrations after batch growth. We examined six bottle sizes (20 to 1,000 ml) using three independent enumeration methods to quantify growth. We found no evidence of a so-called volumetric bottle effect, thus contradicting numerous previous r...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01914-09
更新日期:2010-02-01 00:00:00
abstract::Highly methylated, long-chain celluloses strongly inhibited cellulose degradation by several species of cellulolytic bacteria of ruminal origin. Specifically, the inhibitory effects of methylcellulose on the growth of Ruminococcus flavefaciens FD1 were concentration dependent, with complete inhibition at 0.1% (wt/vol)...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.54.4.890-897.1988
更新日期:1988-04-01 00:00:00
abstract::Laying hens were individually caged at 20 weeks of age and tested for fecal excretion of Campylobacter jejuni (minimum level of detection was 100 cfu/g) during a 42-week period. Peak rates of C. jejuni isolation (approximately 25% of hens positive) occurred at two different times, in October and in late April to early...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.47.3.533-536.1984
更新日期:1984-03-01 00:00:00
abstract::Conjugal transfer of lactose-fermenting ability (Lac+), nisin resistance (Nisr), and phage resistance (Hsp+) was demonstrated in matings between Streptococcus lactis ME2 (donor) and Streptococcus cremoris M43a (recipient), a derivative of M12R. Transconjugants were detected by transfer of Lac+ and were found to exhibi...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.50.4.851-858.1985
更新日期:1985-10-01 00:00:00
abstract::Soil emission of gaseous N oxides during nitrification of ammonium represents loss of an available plant nutrient and has an important impact on the chemistry of the atmosphere. We used selective inhibitors and a glucose amendment in a factorial design to determine the relative contributions of autotrophic ammonium ox...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.56.6.1799-1805.1990
更新日期:1990-06-01 00:00:00
abstract::We analyzed the regional distribution of bulk heterotrophic prokaryotic activity (leucine incorporation) and selected single-cell parameters (cell viability and nucleic acid content) as parameters for microbial functioning, as well as bacterial and archaeal community structure in the epipelagic (0 to 200 m) and mesope...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.07962-11
更新日期:2012-05-01 00:00:00
abstract::Botulinum neurotoxin (BoNT) serotype B (BoNT/B) is one of the serotypes of BoNT that causes deadly human botulism, though it is used clinically for treatment of many neuromuscular diseases. BoNT/B is produced by Clostridium botulinum, and it is secreted along with a group of neurotoxin-associated proteins (NAPs) in th...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00731-10
更新日期:2010-10-01 00:00:00
abstract::A diesel fuel-contaminated aquifer was bioremediated in situ by the injection of oxidants (O2 and NO3-) and nutrients in order to stimulate microbial activity. After 3.5 years of remediation, an aquifer sample was excavated and the material was used (i) to isolate bacterial strains able to grow on selected hydrocarbon...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.63.6.2136-2141.1997
更新日期:1997-06-01 00:00:00
abstract::Wieners and sausages were prepared which contained the most heat-tolerant representative of the Mycobacterium avium-Mycobacterium intracellulare complex we were able to obtain. They also were prepared with infected tissues obtained from tuberculous swine. Processing conditions were as varied as possible. Neither incor...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.38.5.831-835.1979
更新日期:1979-11-01 00:00:00
abstract::Knowledge of host specificity, combined with genomic sequencing of Giardia and Cryptosporidium spp., has demonstrated a microbial source tracking (MST) utility for these common waterborne microbes. To explore the source attribution potential of these pathogens, water samples were collected in a mixed rural-urban water...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02037-13
更新日期:2014-04-01 00:00:00
abstract::The arginine deiminase system was found to function in protecting bacterial cells against the damaging effects of acid environments. For example, as little as 2.9 mM arginine added to acidified suspensions of Streptococcus sanguis at a pH of 4.0 resulted in ammonia production and protection against killing. The argini...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.54.6.1318-1324.1988
更新日期:1988-06-01 00:00:00
abstract::Recently, methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus pseudintermedius (MRSP) have been increasingly isolated from veterinarians and companion animals. With a view to preventing the spread of MRSA and MRSP, we evaluated the occurrence and molecular characteristics of eac...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02780-09
更新日期:2010-08-01 00:00:00
abstract::A gene coding for an aminopeptidase (PepC) from Lactococcus lactis subsp. cremoris AM2 was cloned by complementation of an Escherichia coli mutant lacking aminopeptidase activity. The nucleotide sequence was determined. A portion of the predicted amino acid sequence of PepC (436 amino acids) showed strong homology to ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.59.1.330-333.1993
更新日期:1993-01-01 00:00:00
abstract::The chromate reductase purified from Pseudomonas ambigua was found to be homologous with several nitroreductases. Escherichia coli DH5alpha and Vibrio harveyi KCTC 2720 nitroreductases were chosen for the present study, and their chromate-reducing activities were determined. A fusion between glutathione S-transferase ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.69.8.4390-4395.2003
更新日期:2003-08-01 00:00:00
abstract::Seawater enrichments of marine bacteria clustered in 20- to 50-(mu)m-wide bands near air-water interfaces. The cells within the band travelled at up to 212 (mu)m s(sup-1) and at an average speed of 163 (mu)m s(sup-1). Mean cell speeds peaked mid-run at 187 (mu)m s(sup-1). At the end of the run, bacteria reversed direc...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.62.10.3716-3721.1996
更新日期:1996-10-01 00:00:00
abstract::Although the biological conversion of nitrite to nitrate is a well-known process, studies of Nitrobacter populations are hindered by their physiological characteristics. This report describes a new method for detecting and counting Nitrobacter populations in situ with the PCR. Two primers from the 16S rRNA gene were u...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.61.6.2093-2098.1995
更新日期:1995-06-01 00:00:00
abstract::Strain-specific monoclonal antibodies (MAbs) were developed for three different bacterial isolates obtained from a freshwater environment (Lake Plusssee) in the spring of 1990. The three isolates, which were identified by molecular methods, were as follows: Cytophaga johnsonae PX62, Comamonas acidovorans PX54, and Aer...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.63.11.4534-4542.1997
更新日期:1997-11-01 00:00:00
abstract::Recent functional genomics and genome-scale modeling approaches indicated that B(12) production in Lactobacillus reuteri could be improved by optimization of the medium. Here we show that a series of systematic single-amino-acid omissions could significantly modulate the production of B(12) from nearly undetectable le...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02487-08
更新日期:2009-06-01 00:00:00
abstract::Enzymatic digestion in vitro of the Bacillus thuringiensis protoxin presumably releases and activates the toxin in a manner analogous to that which occurs when a B. thuringiensis sporulated fermentation preparation passes through the midgut of a lepidopteran larva. Therefore, a sporulated culture of B. thuringiensis s...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.53.2.416-421.1987
更新日期:1987-02-01 00:00:00
abstract::Recent isolation of Pseudomonas aeruginosa strains from the open ocean and subsequent pulsed-field gel electrophoresis analyses indicate that these strains have a unique genotype (N. H. Khan, Y. Ishii, N. Kimata-Kino, H. Esaki, T. Nishino, M. Nishimura, and K. Kogure, Microb. Ecol. 53:173-186, 2007). We hypothesized t...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02322-07
更新日期:2008-10-01 00:00:00
abstract::Bacterioplankton numbers, biomasses, and productivities, as well as chlorophyll a concentrations and phytoplankton productivities, were assayed from 1 March 1984 to 12 August 1985 through a 250-m-deep seawater column in Howe Sound, a temperate fjord-sound on the southern coast of British Columbia, Canada. Primary prod...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.53.6.1277-1285.1987
更新日期:1987-06-01 00:00:00
abstract::A fixed-bed loop, high-rate anaerobic bioreactor treating sulfite evaporator condensate was sampled when it reached steady state and afterwards following perturbations during a 14-month period. By using immunotechnology, it was observed that shifts in methanogenic subpopulations occurred in association with perturbati...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.55.8.1996-2001.1989
更新日期:1989-08-01 00:00:00
abstract::The impact of feed supplementation with bambermycin, monensin, narasin, virginiamycin, chlortetracycline, penicillin, salinomycin, and bacitracin on the distribution of Escherichia coli pathotypes in broiler chickens was investigated using an E. coli virulence DNA microarray. Among 256 E. coli isolates examined, 59 (2...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00375-09
更新日期:2009-11-01 00:00:00