Abstract:
:Quorum sensing plays a role in the regulation of soft rot diseases caused by the plant pathogenic bacterium Pectobacterium carotovorum subsp. carotovorum. The signal molecules involved in quorum sensing in P. carotovorum subsp. carotovorum belong to the group of N-acyl homoserine lactones (AHLs). In our study, we screened bacteria isolated from the potato rhizosphere for the ability to degrade AHLs produced by P. carotovorum subsp. carotovorum. Six isolates able to degrade AHLs were selected for further studies. According to 16S rDNA sequence analysis and fatty acid methyl ester profiling, the isolates belonged to the genera Ochrobactrum, Rhodococcus, Pseudomonas, Bacillus, and Delftia. For the genera Ochrobactrum and Delftia, for the first time AHL-degrading isolates were found. Data presented in this study revealed for the first time that Ochrobactrum sp. strain A44 showed the capacity to inactivate various synthetic AHL molecules; the substituted AHLs were inactivated with a lower efficiency than the unsubstituted AHLs. Compared with the other isolates, A44 was very effective in the degradation of AHLs produced by P. carotovorum subsp. carotovorum. It was verified by polymerase chain reaction, DNA-DNA hybridization, and a lactone ring reconstruction assay that Ochrobactrum sp. strain A44 did not possess AHL lactonase activity. AHL degradation in Ochrobactrum sp. strain A44 occurred intracellularly; it was not found in the culture supernatant. AHL-degrading activity of A44 was thermo sensitive. Experiments in planta revealed that Ochrobactrum sp. strain A44 significantly inhibited the maceration of potato tuber tissue. Since A44 did not produce antibiotics, the attenuation of the decay might be due to the quenching of quorum- sensing-regulated production of pectinolytic enzymes. The strain can potentially serve to control P. carotovorum subsp. carotovorum in potato.
journal_name
Can J Microbioljournal_title
Canadian journal of microbiologyauthors
Jafra S,Przysowa J,Czajkowski R,Michta A,Garbeva P,van der Wolf JMdoi
10.1139/w06-062subject
Has Abstractpub_date
2006-10-01 00:00:00pages
1006-15issue
10eissn
0008-4166issn
1480-3275pii
w06-062journal_volume
52pub_type
杂志文章abstract::Antibiotic susceptibility tests and restriction enzyme analysis (REA) of genomic DNA were performed to characterize the relationship between sources of isolates of yellow-pigmented enterococci. Antibiotic susceptibility tests were conducted with 10 therapeutic antibiotics and 54 isolates grouped by source (wild and ot...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-44-11-1066
更新日期:1998-11-01 00:00:00
abstract::To screen, isolate, and characterize bacterial populations producing microcin J25, we report here two rapid, reliable, and sensitive methods, using polymerase chain reaction and colony blot hybridization with a digoxigenin-labelled probe. A sample of 26 Escherichia coli strains isolated from poultry intestinal content...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:
更新日期:2001-09-01 00:00:00
abstract::Increasing the use of nitrogen fertilizers in tea orchards has led to intense nitrous oxide (N2O) emissions. Foliar application of Paenibacillus polymyxa biofertilizer has been proven to be beneficial for organic tea production. In this study, tea yield and quality were significantly improved after application of P. p...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2019-0511
更新日期:2020-03-01 00:00:00
abstract::The ultraviolet germicidal irradiation (UVGI) dose necessary to inactivate fungal spores on an agar surface and the efficacy of UVGI were determined for cultures of Stachybotrys chartarum (ATCC 208877). This study employed a UVGI testing unit consisting of four chambers with a 9-W, Phillips, low pressure, mercury UVGI...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w05-061
更新日期:2005-09-01 00:00:00
abstract::Biological nitrogen fixation (BNF) can be improved by optimizing the interaction between the rhizobial inoculant and pea (Pisum sativum L.), leading to increased productivity and reduced nitrogen (N) fertilizer use. Eight Rhizobium leguminosarum bv. viciae strains were used to inoculate the super-nodulating pea mutant...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2017-0281
更新日期:2017-11-01 00:00:00
abstract::The induction of nitrogenase (C2H2) activity in asymbiotically cultured Rhizobium sp. 32H1 was found to be associated with morphological changes in the cells which were more pronounced than those seen in bacteroids. Polyphosphate granules were found in both bacteroids and cultured cells, but poly-beta-hydroxybutyrate ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m79-055
更新日期:1979-03-01 00:00:00
abstract::Intestinal infections are a major cause of mortality in domestic rabbits. Although a few pathogenic organisms have been associated with this type of infection, it is often impossible to demonstrate the presence of any etiologic agents. Recently viral particles were observed in the intestine of diseased rabbits submitt...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m80-201
更新日期:1980-10-01 00:00:00
abstract::A rapid and efficient electroporation procedure has been developed for transformation of germinating conidia of filamentous fungi. Pretreatment of conidial preparations with a cell wall weakening agent, such as beta-glucuronidase, was found to be essential for successful transformation. Using the qa-2+ gene of Neurosp...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m91-147
更新日期:1991-11-01 00:00:00
abstract::Various soil fungi were tested for their capacity to degrade the insecticide [14C]photodieldrin. Of nine species investigated, Trichoderma viride was the only one which degraded the insecticide to an appreciable extent into water-soluble, non-insecticidal compounds within 4-5 weeks. These products amounted to 32-41% o...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m76-198
更新日期:1976-09-01 00:00:00
abstract::We describe an improved allelic-exchange method for generating unmarked mutations and chromosomal DNA alterations in enterobacterial species. Initially developed for use in Salmonella enterica, we have refined the method in terms of time, simplicity, and efficiency. We have extended its use into related bacterial spec...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w06-102
更新日期:2007-01-01 00:00:00
abstract::Cell-free extracts prepared from the extremely halophilic bacterium Halobacterium saccharovorum oxidize galactose and accumulate a product which reacts as if it were a lactone. The product does not act as a reducing sugar and contains all six of the carbon atoms initially present in galactose. The product was jugged t...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m76-174
更新日期:1976-08-01 00:00:00
abstract::Campylobacter fetus is a recognized pathogen of cattle and sheep that can also infect humans. No adhesins specific for C. fetus have to date been identified; however, bacterial attachment is essential to establish an infecting population. Scanning electron microscopy revealed C. fetus attachment to the serosal surface...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w07-115
更新日期:2008-01-01 00:00:00
abstract::Candida albicans and Saccharomyces cerevisiae cells were examined by scanning scanning electron microscopy before and after extraction of the mannans of the cell wall. The surfaces of control cells were smooth; after mannan extraction they were rough and showed erosions which were particularly striking within the area...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m80-164
更新日期:1980-08-01 00:00:00
abstract::The introduction of the 7-valent pneumococcal vaccine (PCV7) in Canada was very effective in reducing invasive pneumococcal disease (IPD) in children; however, increases of non-PCV7 serotypes have subsequently offset some of these reductions. A 13-valent pneumococcal vaccine (PCV13) targeting additional serotypes was ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2013-0614
更新日期:2013-12-01 00:00:00
abstract::From the four known isoforms of the staphylococcal exfoliative toxins (ETs), only ETA and ETB are the major causative agents. General knowledge is that the gene for ETA is located on the chromosome, whereas that for ETB is located on a large plasmid. Yoshizawa and co-workers (2000, Microbiol. Immunol. 44(3): 189-191) ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2012-0721
更新日期:2013-04-01 00:00:00
abstract::This paper reports two different enterotoxigenic classes of the genus Aeromonas isolated from fishes. Strains of A. sobria were isolated from healthy fishes only wheras strains of A. hydrophila were isolated from both healthy and moribund fishes. Aeromonas sobria and hydrophilia strains produced a cytotoxic factor and...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m77-174
更新日期:1977-09-01 00:00:00
abstract::Nitrogen-fixing, field-obtained root nodules of the silky green alder were studied by transmission electron microscopy. The nodule endophyte exhibited a prokaryotic cytology and was present in two forms: the hypha(0.3-1.0mum), which was branched and septate, and the vesicle (3-5mum), which was also septate and develo...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m75-157
更新日期:1975-07-01 00:00:00
abstract::Early investigation into the mechanism of mitochondriogenesis in the facultative anaerobe Saccharomyces cerevisiae used anaerobic-aerobic transitions as model systems to study the in vivo assembly of these oxidative organelles. This methodology has become entrenched in the early literature and as a result a definitive...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m75-126
更新日期:1975-06-01 00:00:00
abstract::Rhizobia are used exclusively in agricultural systems for enhancing the ability of legumes to fix atmospheric nitrogen. Knowledge about the indigenous population is necessary for the selection and application of inoculant strains. In this study, we have assessed the genetic diversity of Bradyrhizobium strains isolated...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w00-139
更新日期:2001-02-01 00:00:00
abstract::The presence of other soil microorganisms might influence the ability of rhizobacterial inoculants to promote plant growth either by reducing contact between the inoculant and the plant root or by interfering with the mechanism(s) involved in rhizobacterially mediated growth promotion. We conducted the following exper...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w01-080
更新日期:2001-09-01 00:00:00
abstract::We examined factors related to the potent antagonistic effect of Escherichia coli and Bacteroides ovatus on Staphylococcus aureus in anaerobic continuous flow cultures. In the presence of sugars fermentable by E. coli alone or both E. coli and S. aureus, motile E. coli strains exerted a potent antagonistic effect and ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m88-106
更新日期:1988-05-01 00:00:00
abstract::The phyllosphere, which supports a large number of microorganisms, represents the interface between the aboveground parts of plants and air. In this study, four nifH clone libraries were constructed from the phyllosphere of Pyrus serotina (L), Vitis vinifera (P), Prunus armeniaca (X), and Prunus avium (Y). Clones rela...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2018-0588
更新日期:2019-09-01 00:00:00
abstract::Absorption of 14C-labelled poliovirus-2 to sedimentable solids of primary sludge samples collected from a secondary treatment facility during a 6-month period averaged 94%; for anaerobically digested sludge, 99%. The extent of virus adsorption was influenced by the amount of solids. Maximal adsorption occurred at or a...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m83-254
更新日期:1983-12-01 00:00:00
abstract::The induction of antituberculous immunity by crude ribosomal fractions isolated from Mycobacterium tuberculosis strain H37Ra, M. bovis strain BCG, and M. smegmatis was studied in CF-1 mice. Levels of antituberculous immunity similar to that induced by live BCG were induced by the BCG and H37Ra ribosomal fractions wher...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m83-032
更新日期:1983-02-01 00:00:00
abstract::Pestalotiopsis species were most dominant endophytic species isolated from four medicinal plants including Terminalia arjuna, Terminalia chebula, Azadirachta indica, and Holarrhena antidysenterica. Thirty Pestalotiopsis species isolated from different parts of the medicinal plants were selected for the study. The anti...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w08-070
更新日期:2008-09-01 00:00:00
abstract::In the past decade, the large tailings pond (Mildred Lake Settling Basin) on the Syncrude Canada Ltd. lease near Fort McMurray, Alta., has gone methanogenic. Currently, about 60%-80% of the flux of gas across the surface of the tailings pond is methane. As well as adding to greenhouse gas emissions, the production of ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:
更新日期:2000-10-01 00:00:00
abstract::Effects of Trichoderma harzianum and T. polysporum on chlamydospore production by two isolates of Phytophthora cinamomi were determined over a 21-day period in nonsterile, sterilized, and sterilized amended soil. Trichoderma was either coinoculated with P. cinnamomi or added to the cultures on day 3 of the incubation ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m77-042
更新日期:1977-03-01 00:00:00
abstract::Ten bacteriophages infecting Micrococcus luteus have been characterized. All phages contain double-stranded DNA, of 64.3--73.5 mol% guanine plus cytosine (GC). The DNA of phage N7 has the highest GC content reported for any bacterial virus. No unusual bases have been found. The intracellular replicating DNAs of six ph...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m79-158
更新日期:1979-09-01 00:00:00
abstract::Highly distinctive aspects of the exponentail-phase Rhizobium japonicum cell were disclosed by means of thin sections, freeze etching, fluorescent antibodies, and ruthenium red staining. Polarity was expressed in the form of reserve polymer distribution near one end of the cell and as cytoplasmic localization near the...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m77-191
更新日期:1977-09-01 00:00:00
abstract::The phototrophic purple sulfur bacterium Thiopedia rosea forms multicellular, gas-vacuolate, regular, flat aggregates (platelets, sheets) held together by slime. Platelets found in eutrophic water consisted of slime (85% of the total wet volume) and 16 cells, while the gas-filled vacuole occupied 44% of the volume of ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m86-113
更新日期:1986-07-01 00:00:00