Abstract:
:The origin of the eukaryotic nucleus is difficult to reconstruct. While eukaryotic organelles (chloroplast, mitochondrion) are eubacterial endosymbionts, the source of nuclear genes has been obscured by multiple nucleotide substitutions. Using evolutionary parsimony, a newly developed rate-invariant treeing algorithm, the eukaryotic rRNA genes are shown to have evolved from the eocytes, a group of extremely thermophilic, sulfur-metabolizing, anucleate cells. The deepest bifurcation yet found separates the reconstructed tree into two taxonomic divisions. These are a proto-eukaryotic group (karyotes) and an essentially bacterial one (parkaryotes). Within the precision of the rooting procedure, the tree is not consistent with either the prokaryotic--eukaryotic or the archaebacterial--eubacterial--eukaryotic groupings. It implies that the last common ancestor of extant life, and the early ancestors of eukaryotes, very likely lacked nuclei, metabolized sulfur, and lived at near boiling temperatures.
journal_name
Can J Microbioljournal_title
Canadian journal of microbiologyauthors
Lake JAdoi
10.1139/m89-017subject
Has Abstractpub_date
1989-01-01 00:00:00pages
109-18issue
1eissn
0008-4166issn
1480-3275journal_volume
35pub_type
杂志文章abstract::Eight Enterococcus faecium strains isolated from ewe milk and artisanal cheese from northwest Argentina were screened for biotechnological properties relevant to flavour development. The API ZYM test showed absence of proteases, presence of high amounts of peptidases, and high esterase-lipase activities. Low extracell...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w05-136
更新日期:2006-03-01 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::Degradation of purified rubella virus by heat treatment (37, 45, or 56 degrees C) revealed the following structures. The viral envelope, a modified cellular membrane, bears spherical subunits, 5-6 nm in diameter, hexamers, or pentamers. Two glycoproteins, VP-2 (50 000 daltons) and VP-3 (63 000 daltons), are associated...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:
更新日期:1975-05-01 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::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::Sera from mice which have been vaccinated with BCG and challenged with old tuberculin contain gamma interferon. These same sera also express antibacterial activity. Using Staphylococcus aureus we demonstrated that its growth was inhibited at dilutions of sera as high as 1:320. A 4% concentration of sera reduced the gr...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m86-084
更新日期:1986-05-01 00:00:00
abstract::The altitudinal distribution of microfungi associated with Betula ermanii Cham. leaf litter was investigated on Mt. Rishiri (1719 m), northern Japan. Fallen leaves were collected at five sites of different altitudes (approximately 300, 600, 900, 1200, and 1500 m above sea level) along a transect on the northern slope ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w09-030
更新日期:2009-07-01 00:00:00
abstract::Immunovirological studies suggest that human respiratory syncytial virus may well be composed of five structural proteins as are other members of the Paramyxoviridae family: the two external membrane glycoproteins H (90 000) and Fo (F1, 49 000; F2, 20 000; disulfide linked), the internal membrane protein M (34 000), t...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m86-004
更新日期:1986-01-01 00:00:00
abstract::Mucor alternans(van Tieghem) was found to be a diphasic species in that it grew exclusively in the yeast-like budding phase under anaerobic conditions in the complex medium yeast extract-peptone-glucose broth and in tissue-culture medium 199. In the latter medium this growth form occurred also at 37C, at an initial pH...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m75-010
更新日期:1975-01-01 00:00:00
abstract::To determine the seroprevalence of Norwalk virus and whether Norwalk virus contributed to an observed increase in illness in tap water drinkers participating in a prospective epidemiological study, sera collected during the study were examined for changes in Norwalk virus antibody titer, using a specific enzyme immuno...
journal_title:Canadian journal of microbiology
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1139/m94-128
更新日期:1994-10-01 00:00:00
abstract::The effects of pressurized CO2 on the survival of Escherichia coli and the mechanism of cell inactivation were studied. Bacterial cultures were inoculated in nutrient broth and incubated at 30 degrees C for 18 h. Exposure of the cells to CO2 under pressures ranging from 2.5 to 25 MPa and at temperatures between 8 and ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w06-078
更新日期:2006-12-01 00:00:00
abstract::Solid media were used to determine which extracellular hydrolytic enzymes are produced by Phytophthora parasitica; P. parasitica var. nicotianae, races 0, 1, and 3; and several other Phytophthora spp. Most isolates produced RNase, DNase, phosphatase, lipase, and cellulase uniformly. All race 3 isolates of P. parasitic...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m78-015
更新日期:1978-01-01 00:00:00
abstract::Two new yeast species were isolated from flowers of Hibiscus species in Eastern and Northern Australia. Kodamaea kakaduensis is heterothallic, haploid, and similar to other Kodamaea species and to Candida restingae. Buds are often produced on short protuberances, and a true mycelium is formed. The new species differs ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w98-225
更新日期:1999-02-01 00:00:00
abstract::A tryptophan auxotroph of aerobically grown Rodospirillum rubrum was isolated after mutagenesis and replica plating. The mutant grows on tryptophan or indole, accumulates indole glycerol phosphate, lacks the capacity to convert indole glycerol phosphate to indole glycerol phosphate to indole, and finally is defective ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m78-055
更新日期:1978-03-01 00:00:00
abstract::The synthesis of the nucleotide precursors for peptidoglycan is regulated by the relA gene in Escherichia coli. Thus, nucleotide precursors labeled with [3H]diaminopimelic acid accumulated in a relA strain but not in an isogenic relA+ strain during amino acid deprivation. Furthermore, nucleotide precursor synthesis wa...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m82-098
更新日期:1982-06-01 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::The environmental distribution of Giardia spp. and Cryptosporidium spp. is dependent upon human, agricultural, and wildlife sources. The significance of each source with regard to the presence of parasites in the environment is unknown. This 2-year study examined parasite prevalence in human sewage influent, wildlife,...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w02-047
更新日期:2002-06-01 00:00:00
abstract::The use of the food-grade bacterium Lactococcus lactis as a new cell factory is a promising alternative expression system for producing a desired protein. The Omp16-IL2 fusion protein antigen was cloned, expressed, and purified in this study. The Omp16-IL2 fusion gene was designed and cloned in pGH plasmid with approp...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2019-0261
更新日期:2020-01-01 00:00:00
abstract::In an effort to reduce human exposure to adenoviruses through drinking water, we determined the effectiveness of sequential disinfection with an alternative ultraviolet (UV) technology (medium-pressure (MP) UV) and monochloramine. The results of this study showed that MP UV was much more effective than traditional UV ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w10-047
更新日期:2010-07-01 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::Our freshwater caulobacter collection contains about 40 strains that are morphologically similar to Caulobacter crescentus. All elaborate a crystalline protein surface (S) layer made up of protein monomers 100-193 kDa in size. We conducted a comparative study of S-layer secretion in 6 strains representing 3 size group...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w04-046
更新日期:2004-09-01 00:00:00
abstract::Transcriptional profiles of 2 unrelated clinical methicillin-resistant Staphylococcus aureus (MRSA) isolates were analyzed following 10% (v/v) ethanol challenge (15 min), which arrested growth but did not reduce viability. Ethanol-induced stress (EIS) resulted in differential gene expression of 1091 genes, 600 common ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/cjm-2017-0221
更新日期:2017-09-01 00:00:00
abstract::A method to obtain synchronous sporulation during idiophase development in liquid surface cultures of Rhizopus arrhizus Fischer in described and evaluated for use in studying metabolism associated with asexual sporulation. In this system growth and sporulation are effectively separated. The respiratory pattern indicat...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m77-151
更新日期:1977-08-01 00:00:00
abstract::Verticillium fungicola, isolated from Agaricus bisporus (commercial mushroom), produced significant extracellular hydrophobin when grown for 7 days in a static liquid culture of synthetic minimal medium. The hydrophobin was purified by precipitation with ammonium sulphate (80% saturation), Sephadex G-100 gel filtratio...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w02-098
更新日期:2002-11-01 00:00:00
abstract::Polymerase chain reaction amplification was used to compare different regions of the cytochrome c3 gene from nine strains of Desulfovibrio vulgaris, to examine homology within the species. Six 30-base polymerase chain reaction primers and three probes were synthesized on the basis of the published nucleic acid sequenc...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m93-059
更新日期:1993-04-01 00:00:00
abstract::Pathogenic strains of Vibrio cholerae O139 possess the cholera toxin A subunit (ctxA) gene as well as the gene for toxin co-regulated pili (tcpA). We report the isolation of a ctxA-negative, tcpA-negative V. cholerae O139 strain (INDREI) from a patient in Mexico diagnosed with gastrointestinal illness. Certain phenoty...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w03-004
更新日期:2003-01-01 00:00:00
abstract::Soil bacteria that utilize inositol hexaphosphate (IHP) were isolated from a range of soils using defined selection media. An analysis of 200 randomly selected isolates indicated that less than 0.5% of the culturable population of soil bacteria were capable of using IHP as a sole source of C and P. From a further 238 ...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/m97-073
更新日期:1997-06-01 00:00:00
abstract::The study investigated the presence of Borrelia-specific antibodies captured in immune complexes (ICs) in patients with early Lyme disease manifested by erythema migrans. Out of 18 patients, 15 (83.3%) tested positive for polyethylene glycol-precipitated ICs containing IgM antibodies, while only 4 (22.2%) were IgG pos...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/W07-105
更新日期:2007-12-01 00:00:00
abstract::A morphological and physiological description of an anamorphic basidiomycetous yeast species, named Trichosporon guehoae (CBS 8521T), is presented. The ability to assimilate several aliphatic and aromatic compounds as sole source of carbon and energy is reported. The phylogenetic position within the genus, based on nu...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章
doi:10.1139/w99-055
更新日期:1999-08-01 00:00:00
abstract::Bacterial strains and consortia of bacteria have been isolated for their ability to degrade, under anaerobic conditions, homocyclic monoaromatic compounds, such as phenolic compounds, methylbenzenes, and aminobenzenes. As opposed to aerobic conditions where these compounds are degraded via dihydroxyl intermediates int...
journal_title:Canadian journal of microbiology
pub_type: 杂志文章,评审
doi:10.1139/m95-118
更新日期:1995-10-01 00:00:00