Abstract:
:In Salmonella typhimurium LT2 the F factor of Escherichia coli K-12 replicates normally but is repressed; Flac+ cells give no visible lysis on solid media with male-specific phages, low frequency transfer of Flac+ (0.001-0.007 per donor cell), few f2 infective centers (0.002-0.006 per cell), and they propagate male-specific phages to low titers. Thus they display a Fin+ (fertility inhibition) phenotype. This repression, owing to pSLT, a 60 Mdal plasmid normally resident in S. typhimurium, was circumvented by the following materials: (i) Flac+ plasmids from E. coli with mutations in finP or traO; (ii) a S. typhimurium line which had been cured of pSLT; (iii) pKZl, a KmR plasmid in the same Inc group as pSLT, which caused expulsion of pSLT and made Fin- lines; (iv) F-Fin- mutants which originated spontaneously and which are present in most Hfr strains of S. typhimurium. Strains which are derepressed for F function by the above methods give visible lysis on solid media with male-specific phages, ca. 1.0 Lac+ recombinants per donor cell in conjugal transfer, ca. 0.82 f2 infective centers per cell, over 80% of cells with visible F pili, and propagation of male-specific phages to high titer. These data confirm earlier observations that pSLT represses F by the FinOP system. In addition, it shows that there is no other mechanism which represses F function in S. typhimurium. If donor function is derepressed by one of the above methods, and if rough recipient strains are used, F-mediated conjugation in S. typhimurium LT2 is as efficient as in E. coli K-12.
journal_name
Can J Microbioljournal_title
Canadian journal of microbiologyauthors
Sanderson KE,Kadam SK,MacLachlan PRdoi
10.1139/m83-184subject
Has Abstractpub_date
1983-09-01 00:00:00pages
1205-12issue
9eissn
0008-4166issn
1480-3275journal_volume
29pub_type
杂志文章abstract::The purpose of this study was to examine expression and regulation of 6 multidrug efflux systems, including MexAB-OprM, MexCD-OprJ, MexEF-OprN, MexXY, MexJK, and MexVW, in 13 non-cystic fibrosis (CF) clinical isolates of Pseudomonas aeruginosa. These isolates displayed a high level of resistance to many clinically imp...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2014-0239
更新日期:2014-07-01 00:00:00
abstract::The search for new antimicrobial compounds involves finding novel sources of chemotherapeutic compounds or manipulating and combining structures from existing molecules. Small antimicrobial peptides (AMPs) are components of innate immune defenses characterized in greatest detail in insect-derived AMPs. We have generat...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w09-001
更新日期:2009-05-01 00:00:00
abstract::Microsclerotia of three melanin-deficient mutants of Verticillium dahliae formed malanin from (+)-scytalone, 1,8-dihydroxynaphthalene, catechol, and L-3,4-dihydroxyphenylalanine. The melanins formed from (+)-scytalone or 1,8-dihydroxynaphthalene resembled wild-type melanin chemically and ultrastructurally, whereas the...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m78-049
更新日期:1978-03-01 00:00:00
abstract::Isoquinoline is a nitrogen heterocyclic compound that is associated with coal- and oil-derived wastes. Four strains of bacteria able to degrade isoquinoline in pure culture were isolated from sites known to be contaminated with oil. Isoquinoline was used as the sole source of carbon and nitrogen by these isolates. Iso...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m94-089
更新日期:1994-07-01 00:00:00
abstract::Separation of Vero cell membrane in a discontinuous sucrose gradient reveals five fractions. After infection a sixth fraction appears. It contains virioins but mostly modified membranes with subunits 5-6 nm in diameter, probably the hemagglutinin. None of the enzymes used was associated with this fraction. No modifica...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m75-103
更新日期:1975-05-01 00:00:00
abstract::Fluorescent antibody was prepared against a temperate-soil isolate of Beijerinckia obtained from a rhizosphere of rice growing in Camargue (France). The antibody did not cross-react with any of 6 species of Azotobacter, 4 species of Beijerinckia, or 44 unidentified soil bacteria isolated from a spectrum of rhizosphere...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m77-023
更新日期:1977-02-01 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::The respiration of Candida lipolytica on n-tetradecane is decreased in the presence of bentonite. This inhibition is less pronounced by the introduction of hydrophobic chains on the bentonite. Oxygen demand of resting cells varies with the length of hydrophobic chains. In fermentor, addition of adsorbant does not stim...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:
更新日期:1976-08-01 00:00:00
abstract::Vibrio cholerae activates proinflammatory response in cultured intestinal epithelial cells. In this study, we demonstrate that V. cholerae O395 infection of intestinal epithelial cells results in the activation of Akt. Inhibition of Akt significantly decreases IL-1alpha, IL-6, and TNF-alpha production in V. cholerae i...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w09-093
更新日期:2009-11-01 00:00:00
abstract::Colletotrichum gloeosporioides is the causal agent of rubber tree anthracnose and leads to serious losses of natural rubber production. The pathogenesis of C. gloeosporioides on rubber tree remains unknown. Cerato-platanin proteins are small, secreted cysteine-rich proteins that contribute to virulence and function in...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2018-0087
更新日期:2018-11-01 00:00:00
abstract::Chitinases isolated from membrane and cytosolic fractions of two mucoraceous fungi, Choanephora cucurbitarum and Phascolomyces articulosus, were investigated. The membrane-bound chitinase was isolated by Bio-Gel P-100 and DEAE Bio-Gel A chromatographic techniques. On SDS-PAGE the chitinase from both fungi migrated as ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m92-056
更新日期:1992-04-01 00:00:00
abstract::The immune benefits associated with the optimal intake of dietary fatty acids are widely known. The objective of the present investigation was to elucidate the role of omega-3 polyunsaturated fatty acids (n-3 PUFA) food source on acute pneumonia induced by Klebsiella pneumoniae. Three different n-3 PUFA preparations (...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2012-0521
更新日期:2013-07-01 00:00:00
abstract::Salmonella typhimurium and a series of rough lipopolysaccharide mutants derived from it were used as target bacteria to examine the antimicrobial capacity of magainin 2. Magainin 2 demonstrated a dose-related bactericidal activity against the smooth parent strain and the series of lipopolysaccharide mutants. The lipop...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m90-102
更新日期:1990-08-01 00:00:00
abstract::The open reading frame pp0053, which has a high homology with the sequence of mitochondrial sulfide dehydrogenase (HMT2) conferring cadmium tolerance in fission yeast, was amplified from Pseudomonas putida KT2440 and expressed in Escherichia coli JM109(DE3). The isolated and purified PP0053-His showed absorption spect...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w06-022
更新日期:2006-08-01 00:00:00
abstract::Fourteen Lactococcus lactis strains showing inhibitory activity against Listeria innocua SICC 4202 were isolated from different French raw milks and raw milk cheeses and screened for bacteriocin production by the triple layer method under conditions that eliminate the effects of lactic acid and hydrogen peroxide. Thre...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m95-114
更新日期:1995-09-01 00:00:00
abstract::Fifty-four strains of Neisseria gonorrhoeae were examined for their ability to be agglutinated by various lectins. Wheat germ agglutinin, ricin, soybean lectin, and peanut agglutinin agglutinated all strains tested. Dolichos biflorus, Sophora japonica, Maclura pomifera, Ulex Europaeus, Lens culinaris, Canavalia ensifo...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m80-078
更新日期:1980-04-01 00:00:00
abstract::A test is described for selective inhibition of Mycobacterium tuberculosis and M. bovis isolates in fluid medium. The method employs rho-nitro-alpha-acetyl-amino-beta-hydroxy-propiophenone (NAP) as an inhibitory agent for differentiation of mammalian tuberculosis strains from other Mycobacteria. ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m78-124
更新日期:1978-06-01 00:00:00
abstract::Characterization and enumeration of the adherent epimural community of the rumen wall of young, conventionally reared lambs were carried out from 2 to 21 days after birth. Three hundred strains were isolated by anaerobic procedures from three sites: dorsal, ventral, and caudal sacs, and from the sloughed epithelial ce...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m89-114
更新日期:1989-07-01 00:00:00
abstract::Nodulation of Pisum sativum cv. Afghanistan by Rhizobium leguminosarum strain Tom can be blocked by the nonnodulating R. leguminosarum strain PF2. This system was used to study the dynamics of rhizobial binding to seedling root surfaces. Appreciable numbers of 35S-labeled rhizobia bound to the root surface within 2h a...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m80-099
更新日期:1980-04-01 00:00:00
abstract::Agricultural practices such as manure applications could contribute to the spread of antibiotic resistance genes (ARGs) within the environment. Our objective was to assess the impact of certain fertilization methods (mineral or manure) and tillage practices (reduced or conventional) on the presence of ARGs and bacteri...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2019-0343
更新日期:2020-10-01 00:00:00
abstract::Twenty-six strains of group JK corynebacteria had the same colonial morphology and biological reactions as the biotypes of the biovars of Corynebacterium genitalium and C. pseudogenitalium. Therefore, group JK corynebacteria can be assigned to the biovars of C. genitalium or C. pseudogenitalium. Although the strains d...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m84-164
更新日期:1984-08-01 00:00:00
abstract::Human astrovirus (HAstV) was an important cause of viral gastroenteritis in infants in Wuhan city based on our previous study. The aim of the study was to investigate the nature of HAstV infection in Wuhan, People's Republic of China, especially in adults. Stool specimens were collected from 361 children and 301 adult...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w11-085
更新日期:2011-11-01 00:00:00
abstract::Aluminum (Al) toxicity is a major problem affecting soil fertility, microbial diversity, and nutrient uptake of plants. Rhizobia response and legume interaction under Al conditions are still unknown; it is important to understand how to develop and improve legume cultivation under Al stress. In this study, rhizobia re...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2018-0019
更新日期:2018-08-01 00:00:00
abstract::The purpose of this study was to examine antimicrobial activity of endophytic fungi isolated from the leaves, stems, and roots of 54 species of Orchidaceae collected in a Brazilian tropical ecosystem. In total, 382 filamentous fungi and 13 yeast isolates were obtained and cultured to examine the production of crude ex...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/W09-101
更新日期:2009-12-01 00:00:00
abstract::The oomycetes, a distinct phylogenetic lineage of fungus-like microorganisms, are heterokonts (stramenopiles) belonging to the supergroup Chromalveolata. Although the complete genomic sequences of a number of oomycetes have been reported, little information regarding the introns therein is available. Here, we investig...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w10-103
更新日期:2011-02-01 00:00:00
abstract::Agroinfiltration is used to treat plants with modified strains of Agrobacterium tumefaciens for the purpose of transient in planta expression of genes transferred from the bacterium. These genes encode valuable recombinant proteins for therapeutic or industrial applications. Treatment of large quantities of plants for...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2020-0239
更新日期:2021-01-01 00:00:00
abstract::Growth rates and cell yields of Mycobacterium convolutum strain R22 grown on a wide range of both odd- and even-numbered carbon solid n-alkanes decreased as the substrate carbon number increased. Cellular lipid was 2.5 times higher following growth on the hydrocarbon substrates. The amount of polar lipid was found to ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m78-194
更新日期:1978-10-01 00:00:00
abstract::Pathogenic and nonpathogenic isolates of Venturia inaequalis were grown in liquid culture. Hyphae were treated with two types of fimbrial antiserum (AU- and AV-1) and examined by immunofluorescent microscopy, in order to establish the distribution of fimbrial epitopes in whole cell mounts. The AV-1 antiserum was speci...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w00-061
更新日期:2000-09-01 00:00:00
abstract::The effects of seven thiophosphorus pesticides and their degradation products on estuarine ammonium oxidizers were examined. Using an axenic, closed-culture, high cell density assay, the pesticides caused little inhibition of ammonium oxidation. However, the degradation product of methyl parathion, p-aminophenol, sign...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m80-216
更新日期:1980-11-01 00:00:00
abstract::Pleomorphic deterioration is a process where a fungal isolate loses the ability to produce conidia during repeated subculturing. We have previously isolated strains of the entomopathogenic fungus Metarhizium anisopliae that have irreversibly lost the ability to produce conidia and only produce mycelia when grown on ag...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w02-074
更新日期:2002-09-01 00:00:00