Abstract：
:The effect of hydrogen peroxide on Treponema pallidum was investigated. The in vitro loss of virulence (as measured by rabbit inoculation) of T. pallidum was accelerated by as low as 100 microM hydrogen peroxide in the complex maintenance medium used. Higher doses led to rapidly accelerated death with 500 microM hydrogen peroxide causing sterilization of the medium within 3 to 4 h. Since hydrogen peroxide is known to cause single-stranded breaks in DNA, the effect of hydrogen peroxide on the treponemal genome was examined. Extensive breakage was caused by 100 microM hydrogen peroxide as determined on alkaline sucrose gradients. A limit was reached at 250 microM and above. Single-stranded breaks could be demonstrated as early as 5-10 min after exposure to hydrogen peroxide when the treponemes were exposed to 250 microM hydrogen peroxide; accelerated death was evident by 2 h past exposure demonstrating that DNA breakage was preceding death. Treponemal death caused by penicillin did not result in DNA breakage. The repair-proficient bacterium Escherichia coli K-12 was compared with T. pallidum. It required 10-100 times more hydrogen peroxide to cause various levels of breakage. Escherichia coli K-12 rapidly repaired DNA breakage once hydrogen peroxide was removed by addition of catalase. Treponema pallidum, in comparison, showed little or no repair in vitro. Addition of catalase or dithiothreitol to the medium protected against all but a low level of breakage; this may reflect on the ability of catalase and reducing agents to protect T. pallidum against oxygen toxicity in vitro.
journal_name
Can J Microbioljournal_title
Canadian journal of microbiologyauthors
Steiner BM,Wong GH,Sutrave P,Graves Sdoi
10.1139/m84-234subject
Has Abstractpub_date
1984-12-01 00:00:00pages
1467-76issue
12eissn
0008-4166issn
1480-3275journal_volume
30pub_type
杂志文章abstract：:The use of two pulsed lasers as excitation sources in the immunofluorescent technique FTA-ABS (fluorescent treponemal antibody absorption) shows that excitation of specimens by continuous or long-duration pulses of light (in the order of a millisecond) degrades the fluorescence in such a way that it is impossible to q...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：
更新日期：1975-08-01 00:00:00
abstract：:In the frame of a survey of potentially endophytic N2-fixing Burkholderia associated with maize in Mexico, its country of origin, the soil of an indigenous maize field near Oaxaca was studied. Under laboratory conditions, plant seedlings of two ancient maize varieties were used as a trap to select endophyte candidates...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/w02-023
更新日期：2002-04-01 00:00:00
abstract：:Grapes inoculated with poliovirus 1 and coxsackievirus B5 were washed with water, 0.5% polyehtylene glycol, or phosphate-buffered saline with 1% serum. These washes were equally efficient at removing virus but much of the virus in the water was noninfectious until treated with 0.5% polyethylene glycol. ...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m77-195
更新日期：1977-09-01 00:00:00
abstract：:The aim of this study was to determine possible differences in the faecal microbiota of dairy cows infected with Mycobacterium avium subsp. paratuberculosis (Johne's disease) in comparison with noninfected cows from the same herds. Faecal samples from cows in 4 herds were tested for M. avium subsp. paratuberculosis by...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/cjm-2015-0814
更新日期：2016-06-01 00:00:00
abstract：:Approximately 20% of Canada's oil supply now comes from the extraction of bitumen from the oil sands deposits in northeastern Alberta. The oil sands are strip-mined, and the bitumen is typically separated from sand and clays by an alkaline hot water extraction process. The rapidly expanding oil sands industry has mill...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/w01-129
更新日期：2002-01-01 00:00:00
abstract：:Four modes of heating endotoxin in plasma and two different times of heating endotoxin in pyrogen-free water were compared. There were no significant differences in standard curves after heating endotoxin in plasma at 100 degrees C for 1 and for 10 min. However, the standard curve after heating for 10 min at 75 degree...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m86-140
更新日期：1986-10-01 00:00:00
abstract：:Mixtures of anionic HgCl3-/HgCl4(2)-complexes were less toxic to terrestrial bacteria (Erwinia herbicola, Agrobacterium tumefaciens), to marine bacteria (Acinetobacter sp., Aeromonas sp.), and to bacteriophages (phi 11 M 15 of Staphylococcus aureus and P1 of Escherichia coli) than were equivalent concentrations of Hg ...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m79-197
更新日期：1979-11-01 00:00:00
abstract：:During exponential growth, strain AW405 of Escherichia coli K-12 did not regulate the fatty acid composition of its lipids in response either to temperature or to the addition of NaCl, KCl, or MgCl2 to the medium. Growth was severely restricted at temperatures below 21 degrees C. Differential scanning calorimetry (DSC...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m81-128
更新日期：1981-08-01 00:00:00
abstract：:In the dairy industry, bacterial contaminants persist on equipment surfaces due to spore and biofilm formation. These are involved in cross-contamination problems that affect the quality of processed products and limit their life. The pasteurization process, in which milk is submitted to moderate heat treatment, is in...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章,评审
doi：10.1139/cjm-2018-0435
更新日期：2019-06-01 00:00:00
abstract：:From electron-microscopical observations, a decreased metabolic activity in 3-day-old Candida albicans chlamydospores was suggested, and progressive deterioration in chlamydospores aged 2-8 months was shown. Oxygen utilization by chlamydospore-pseudomycelium (CSP) preparations was less than that by yeast, while 3-day-...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m79-111
更新日期：1979-06-01 00:00:00
abstract：:The diversity and variation of total and active ammonia-oxidizing bacteria in a full-scale aerated submerged biofilm reactor for drinking water pretreatment were characterized by clone libraries and denaturing gradient gel electrophoresis (DGGE) analysis of 16S rRNA and its gene during a whole year. Sequences obtained...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/w08-011
更新日期：2008-05-01 00:00:00
abstract：:The ruminal microbiota plays major roles in feed digestion. The composition and fermentation of the bacterial communities in 3 important ruminant species have been studied previously. Here, we extended this research to the effect of concentrate-to-forage ratios on ruminal bacterial communities in Tarim red deer (Cervu...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/cjm-2018-0046
更新日期：2018-07-01 00:00:00
abstract：:Neisseria polysaccharea (LNP 462, NCTC 11858), proposed as a prototype strain constituting a new taxon in the genus Neisseria, produces copious amounts of polysaccharide when grown on agar containing 1-5% sucrose. Plate-grown cells produced an exocellular polysaccharide which was composed of D-glucose, had [alpha]D +2...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m86-167
更新日期：1986-12-01 00:00:00
abstract：:A species of Arthrobacter was recovered during culture of the causal organism of pitch canker of southern pines. Fusarium moniliforme var. subglutinans (FMS). Arthrobacter is a relatively common soil bacterium and is lytic to several fungal pathogens in the soil. Soil samples from two seed orchards with pitch canker a...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m81-004
更新日期：1981-01-01 00:00:00
abstract：:The Bacillus subtilis glutamyl-tRNA synthetase (GluRS), encoded by the gltX gene, aminoacylates its homologous tRNA(Glu) and tRNA(Gln) with glutamate. This gene was cloned with its sigma A promoter and a downstream region including a rho-independent terminator in the shuttle vector pRB394 for Escherichia coli and B. s...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：
更新日期：1998-04-01 00:00:00
abstract：:The regulation of de novo pyrimidine biosynthesis in Pseudomonas putida ATCC 17536 by pyrimidines was explored. The pathway enzyme activities were higher in glucose-grown cells than in succinate-grown cells, indicating catabolite repression by succinate. In P. putida cells grown on succinate as a carbon source, only a...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/w02-110
更新日期：2002-12-01 00:00:00
abstract：:Forty different antibiotics with diverse kingdom and functional specificities were used to measure the functional characteristics of the archaebacterial translation apparatus. The resulting inhibitory curves, which are characteristic of the cell-free system analyzed, were transformed into quantitative values that were...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m89-021
更新日期：1989-01-01 00:00:00
abstract：:A defined medium (CDM) is described which supported growth and sporulation of type E strains of Clostridium botulinum, but not sporulation of other serotypes of C. botulinum or C. sporogenes. As compared to growth in complex medium, spore outgrowth was delayed and both the growth rate and the cell yield was reduced. H...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m79-076
更新日期：1979-04-01 00:00:00
abstract：:To isolate thiamine excretors and (or) overproducers, 188 cultures belonging to nine yeast and three fungal genera were screened. Nine excreted thiamine as determined by both the presence of cross-feeding zones on a thiamine-free agar medium seeded with a thiamine-requiring yeast strain and by the direct detection of ...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m92-189
更新日期：1992-11-01 00:00:00
abstract：:Vaccination is the most promising strategy to reduce the incidence of pneumococcal infection. Although there are vaccines available, all of them are based on polysaccharide antigens (conjugated or not). In addition to their high cost, those vaccines do not cover all serotypes. To overcome these hindrances, we evaluate...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/w2012-083
更新日期：2012-09-01 00:00:00
abstract：:Marine shrimp of the species Penaeus monodon were collected from the coastal region (Haroa) of the deltaic Sundarbans of West Bengal, India during the premonsoon period in 1996. Klebsiella pneumoniae was isolated from the alimentary canal and gills of the shrimp as the sole isolate. All 10 isolated strains were resist...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：
更新日期：1998-02-01 00:00:00
abstract：:A strain of Pseudomonas putida grew rapidly on cyclohexanecarboxylic acid as a sole source of carbon. A CoA-mediated beta-oxidation pathway was induced for the metabolism of the compound. The organism could not utilize 3-cyclohexenecarboxylic acid as a sole source of carbon for growth, but cells grown on gluconate in ...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m82-198
更新日期：1982-12-01 00:00:00
abstract：:The possibility of using the volatile-producing fungus Muscodor albus for biofumigation against building molds was investigated. Several species of Aspergillus and Penicillium as well as fungi belonging to nine other genera were inhibited or killed in vitro by volatiles produced by potato dextrose agar or rye grain cu...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/W06-124
更新日期：2007-03-01 00:00:00
abstract：:Porcine epidemic diarrhea virus (PEDV) causes severe infectious diseases in all ages of swine and leads to serious economic losses. Serologic tests are widely accepted and used to detect anti-PEDV antibodies that could indicate PEDV infection or vaccination. In this study, PEDV recombinant S1 protein (rS1) was express...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/cjm-2018-0240
更新日期：2019-05-01 00:00:00
abstract：:Isolated toluene-degrading Pseudomonas stutzeri ST-9 bacteria were grown in a minimal medium containing toluene (100 mg·L(-1)) (MMT) or glucose (MMG) as the sole carbon source, with specific growth rates of 0.019 h(-1) and 0.042 h(-1), respectively. Scanning (SEM) as well as transmission (TEM) electron microscope anal...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/cjm-2016-0099
更新日期：2016-08-01 00:00:00
abstract：:Deoxyribonuclease (DNase) activity was found in the culture fluids of numerous marine bacteria isolated from seawater. Among these ogranisms, marine bacterium, Vibrio sp., strain No. 2, showed the highest deoxyribonucleic acid-hydrolyzing activity. This organism requires salts of seawater for both growth and extracell...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m76-213
更新日期：1976-10-01 00:00:00
abstract：:The peptidoglycan of Escherichia coli K-12 strain AB264 was isolated by treating whole cells with sodium dodecyl sulfate and was purified by deoxyribonuclease, ribonuclease, and trypsin treatment. Like the peptidoglycan of Bacillus subtilis, this peptidoglycan proved able to bind substantial amounts of metallic ions f...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m84-031
更新日期：1984-02-01 00:00:00
abstract：:Raw milk samples from bulk tanks in Ontario were analyzed for the presence of Listeria species. The overall incidence of Listeria species in raw milk was 12.4%. Listeria innocua was most frequently isolated and was found in 9.7% (43/445) of the raw milk samples, while L. monocytogenes and L. welshimeri were each found...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m88-020
更新日期：1988-02-01 00:00:00
abstract：:A study has been undertaken to account for the presence of Thiobacillus acidophilus in iron-grown cultures of Thiobacillus ferrooxidans. Attempts to adapt T. acidophilus to ferrous iron were not successful but the facultative autotroph grew to a limited extent in the spent medium of T. ferrooxidans and was able to gro...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m80-178
更新日期：1980-09-01 00:00:00
abstract：:The release of 14CO2 from 14C-labelled glucose(G-1(-14)C, G-3,4(-14)C, G-6(-14)C) was followed in phased cultures of Candida utilis grown in a glucose- mineral salts medium under altered conditions of carbon:nitrogen limitation at doubling times of 2,4 and 6, h. Changes in oxygen uptake and CO2 evolution were observe...
journal_title：Canadian journal of microbiology
pub_type： 杂志文章
doi：10.1139/m75-150
更新日期：1975-07-01 00:00:00
