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1.
A rod-shaped, gram-negative bacterium Stenotrophomonas sp. SMSP-1 was isolated from the sludge of a wastewater treating system of a pesticide manufacturer. Strain SMSP-1 could
hydrolyze methyl parathion to p-nitrophenol (PNP) and dimethyl phosphorothioate but could not degrade PNP further. Strain SMSP-1 was able to hydrolyze other
organophosphate pesticides, including fenitrothion, ethyl parathion, fenthion, and phoxim, but not chlorpyrifos. A 4395-bp
DNA fragment, including an organophosphorus hydrolase encoding gene ophc2, was cloned from the chromosome of strain SMSP-1 using the shotgun technique. Its sequence analysis showed that ophc2 was associated with a typical mobile element ISPpu12 consisting of tnpA (encoding a transposase), lspA (encoding a lipoprotein signal peptidase), and orf1 (encoding a CDF family heavy metal/H+ antiporter). The ophc2 gene was effectively expressed in E. coli. This is the second report of cloning the ophc2 gene and the first report of this gene from the genus of Stenotrophomonas. 相似文献
2.
M. A. Veselova 《Russian Journal of Genetics》2010,46(2):129-137
Expression of many bacterial genes is regulated in a cell density-dependent manner via small signal molecules known as autoinducers;
this type of regulation is termed quorum sensing (QS). The QS systems that employ N-acyl-homoserine lactones (HSLs) are best un derstood in Gram-negative bacteria. QS regulates expression of various genes,
including the genes responsible for the production of virulence factors, synthesis of exoenzymes and antibiotics, antagonistic
properties of bacteria, etc. The QS systems of the genus Pseudomonas are linked to other global regulatory networks of the cell, and their functions are controlled by numerous additional regulatory
factors. Such regulators and the QS systems together form an intricate multifactorial cascade regulatory network. The review
considers the QS systems of several Pseudomonas species, their interaction with other regulatory systems, and their roles in the regulation of cell processes. 相似文献
3.
Pseudomonas sp. strain WBC-3 utilizes para-nitrophenol (PNP) as a sole source of carbon, nitrogen and energy. PnpA (PNP 4-monooxygenase) and PnpB (para-benzoquinone reductase) were shown to be involved in the initial steps of PNP catabolism via hydroquinone. We demonstrated
here that PnpA also catalyzed monooxygenation of 4-nitrocatechol (4-NC) to hydroxyquinol, probably via hydroxyquinone. It
was the first time that a single-component PNP monooxygenase has been shown to catalyze this conversion. PnpG encoded by a
gene located in the PNP degradation cluster was purified as a His-tagged protein and identified as a hydroxyquinol dioxygenase
catalyzing a ring-cleavage reaction of hydroxyquinol. Although all the genes necessary for 4-NC metabolism seemed to be present
in the PNP degradation cluster in strain WBC-3, it was unable to grow on 4-NC as a sole source of carbon, nitrogen and energy.
This was apparently due to the substrate’s inability to trigger the expression of genes involved in degradation. Nevertheless,
strain WBC-3 could completely degrade both PNP and 4-NC when PNP was used as the inducer, demonstrating its potential in bioremediation
of the environment polluted by both 4-NC and PNP. 相似文献
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5.
A leaf beetle, Crioceris sp. (Coleoptera: Chrysomelidae), was introduced into Australia as a biological control agent of bridal creeper (Asparagus asparagoides L. Druce) during October 2002. Rearing of Crioceris sp. is labour intensive therefore all releases of Crioceris sp. have been under 1000 individuals, which may be too low to ensure establishment if high mortality and high competition
with other agents occurs. The aim of this study is to understand how the presence of two well-established biocontrol agents,
a rust fungus (Puccinia myrsiphylli (Thuem) Wint [Basidiomycota: Uredinales]) and a leafhopper (Zygina sp. [Hemiptera: Cicadellidae]), might influence Crioceris sp. establishment. Crioceris sp. neonate larvae were placed on bridal creeper plants with or without the leafhopper and/or rust. The number of larvae
that pupated was reduced by 38 and 65% in the presence of the rust fungus and leafhopper, respectively and by 45% in the presence
of both agents. As the area infected by the rust increased the area damaged by the leafhopper decreased. The rust appeared
to be negatively impacted by the presence of the leafhopper. In a second experiment, female Crioceris sp. adults were given a choice between uninfested bridal creeper plants and those infested with the rust or the leafhopper.
The females preferred to lay their eggs on plants without leafhoppers but did not seem to be deterred by the presence of the
rust. Consequently, the performance and impact of Crioceris sp. on bridal creeper may be reduced if populations overlap with the other biocontrol agents in the field. 相似文献
6.
O. V. Golovanova V. I. Konenkov A. V. Shevchenko M. V. Smolnikova 《Russian Journal of Genetics》2009,45(8):981-986
Based on population analysis of the DRB1, DQA1, DQB1 and TNFA allele frequency distribution patterns, regional features of immunogenetic structure of the population of West Siberia were
investigated. Statistically significant linkage disequilibrium within the HLA class II region, as well as between the TNFA and DRB1, DQA1, and DQB1 was demonstrated. Population frequency distribution patterns of two- and multilocus haplotypes were examined. 相似文献
7.
Hiroyoshi Kubo 《Mycoscience》2009,50(5):400-406
Pilobolus crystallinus shows unique photoresponses at various growing stages. cDNAs for putative photoreceptors were cloned from this fungus. Three
genes named pcmada1, pcmada2, and pcmada3 were identified from the PCR fragments, and amplified with degenerated primers for the LOV domain, which is conserved in
many blue-light receptors. Deduced amino acid sequences for PCMADA1, PCMADA2, and PCMADA3 had one light-oxygen-voltage (LOV)-sensing
and two PER-ARNT-SIM (PAS) domains. A zinc finger DNA-binding motif was conserved in the C-terminals of PCMADA1 and PCMADA3.
However, PCMADA2 lacked the zinc finger motif. Expression of pcmada1 was suppressed by blue light whereas that of pcmada3 was promoted by blue-light irradiation. 相似文献
8.
Microbial fuel cells (MFCs) are a technology that provides electrical energy from the microbial oxidation of organic compounds.
Most MFCs use oxygen as the oxidant in the cathode chamber. This study examined the formation in culture of an unidentified
bacterial oxidant and investigated the performance of this oxidant in a two-chambered MFC with a proton exchange membrane
and an uncoated carbon cathode. DNA, FAME profile and characterization studies identified the microorganism that produced
the oxidant as Burkholderia cenocepacia. The oxidant was produced by log phase cells, oxidized the dye 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS),
had a mass below 1 kD, was heat stable (121°C) and was soluble in ethanol. In a MFC with a 1000 Ω load and ABTS as a mediator,
the oxidizer increased cell voltage 11 times higher than atmospheric oxygen and 2.9 times higher than that observed with ferricyanide
in the cathode chamber. No increase in cell voltage was observed when no mediator was present. Organisms that produce and
release oxidizers into the media may prove useful as bio-cathodes by improving the electrical output of MFCs. 相似文献
9.
S. Rehman A. S. Shawl A. Kour R. Andrabi P. Sudan P. Sultan V. Verma G. N. Qazi 《Applied Biochemistry and Microbiology》2008,44(2):203-209
The medicinal plant, Nothapodytes foetida, contains a number of important alkaloids like camptothecin (an anticancer drug molecule), but its concentration is less
to meet the existing demand of this important molecule, in an effort for accessible availability of camptothecin. An endophyte
(designated ZP5SE) was isolated from the seed of Nothapodytes foetida and was examined as a potential source of anticancer drug lead compound, i.e., camptothecin, when grown in Sabouraud liquid
culture media under shake flask conditions. The presence of an anticancer compound (camptothecin) in this fungus was confirmed
by chromatographic and spectroscopic methods in comparison with authentic camptothecin. Isolated endophyte (Neurospora crassa) producing camptothecin may become an easily accessible source for the production of a precursor anticancer drug molecule
in the future at a large scale.
Published in Russian in Prikladnaya Biokhimiya i Mikrobiologiya, 2008, Vol. 44, No. 2, pp. 225–231.
The text was submitted by the authors in English. 相似文献
10.
There are three most important bacterial causative agents of serious infections that could be misused for warfare purposes:
Bacillus anthracis (the causative agent of anthrax) is the most frequently mentioned one; however, Fracisella tularensis (causing tularemia) and Yersinia pestis (the causative agent of plague) are further bacterial agents enlisted by Centers for Disease Control and Prevention into the category A of potential biological weapons. This review intends to summarize basic information about these bacterial
agents. Military aspects of their pathogenesis and the detection techniques suitable for field use are discussed. 相似文献
11.
Septobasidium parviflorae sp. nov. on Pinus parviflora is described and illustrated. This species is characterized by its whitish-gray, gray to dark gray-colored fungus body with
an indeterminate margin, hyphal strands, and cylindrical basidia with long sterigmata. This is the first report of Septobasidium occurring on a member of the genus Pinus in Japan. 相似文献
12.
Bin Zhang DanDan Jiang WenWen Zhou HuaKun Hao TianGui Niu 《World journal of microbiology & biotechnology》2009,25(4):583-590
A new native feather-degrading bacterium has been isolated from the faeces of the agamid lizard Calotes versicolor, collected from the Beijing Zoo in China. The isolate, which has been identified as Bacillus sp. 50-3 based on morphological and biochemical and 16S rDNA tests, was shown to degrade native feather completely at 37°C
and pH 7.0 within 36 h when using chicken feathers as the sole carbon and nitrogen source. Bacillus sp. 50-3 presented optimum growth at 37°C and pH 7.0 in feather meal medium. Under these conditions, the maximum keratinase
activity (680 ± 25 U/ml) was also achieved. The keratinase of Bacillus sp. 50-3 was active over a broad range of pH values and temperatures toward azokeratin, and presented an optimum pH and temperature
of 10.0 and 60°C, respectively. Furthermore, it was relatively heat-and alkali-stable. Inhibitor studies showed that it seemed
to belong to the serine-metalloprotease type. Therefore, the enzyme from Bacillus sp. 50-3 is a novel, high alkaline keratinase, suggesting its potential use in biotechnological processes. 相似文献
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14.
Moslem Papizadeh Mohammad Roayaei Ardakani Gholamhossein Ebrahimipour Hossein Motamedi 《World journal of microbiology & biotechnology》2010,26(7):1195-1200
Oil-polluted soils were sampled from National Iranian South Oil Company (NISOC) for isolation and screening of C–S and not
C–C targeted Dibenzothiophene (DBT) degrading microorganisms. Microbacterium sp. NISOC-06, a C–S targeted DBT degrading bacterium, was selected and its desulfurization ability was studied in aqueous phase and water-gasoline
biphasic systems. The 16srRNA gene was amplified using universal eubacteria-specific primers, PCR product was sequenced and
the sequence of nearly 1,500 bp 16srDNA was studied. Based on Gas Chromatography results Microbacterium sp. NISOC-06 utilized 94.8% of 1 mM DBT during the 2 weeks of incubation. UV Spectrophotometry and biomass production measurements showed
that the Microbacterium sp. NISOC-06 was not able to utilize DBT as a carbon source. There was no accumulation of phenolic compounds as Gibb’s assay showed. Biomass
production in a biphasic system for which DBT-enriched gasoline was used as the sulfur source indicated the capability of
Microbacterium sp. NISOC-06 to desulfurize gasoline. 相似文献
15.
Sathyanarayana N. Gummadi Swati Sucharita Dash Santhosh Devarai 《Journal of industrial microbiology & biotechnology》2009,36(5):713-720
The effect of pH, aeration rate, and agitation rate on specific productivity of caffeine demethylase from Pseudomonas sp. was studied in a bioreactor. Maximum specific productivity of caffeine demethylase of 2,214 U g cell dry weight−1 h−1 was obtained at 0.27 vvm, 700 rpm, and pH 7.0. Under these conditions, volumetric oxygen transfer coefficient was 74.2 h−1, indicating that caffeine demethylase production by Pseudomonas sp. was highly oxygen-dependent. Different metabolite formation at different agitation and aeration rates can be used as
a strategy for recovery of pharmaceutically important metabolites from caffeine by manipulation of conditions in a bacterial
culture. This is the first report on production of high levels of caffeine demethylase in bioreactors. 相似文献
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18.
N. Yu. Markelova 《Microbiology》2010,79(6):777-779
Interaction of Bdellovibrio bacteriovorus 100NCJB with bacteria Campylobacter jejuni (strains 1, 2, 3, 4, and 5) and Helicobacter pylori, strain TX30a, was confirmed. The results indicate that lytic activity of bdellovibrios both in liquid media and cells attached
to a surface was observed. The potential use of the antimicrobial activity of predatory bacteria for environmental bioprotection
and public health is discussed. 相似文献
19.
N. S. Utkina L. L. Danilov T. N. Druzhinina V. V. Veselovskii 《Russian Journal of Bioorganic Chemistry》2010,36(6):783-785
A simple method of the synthesis of P
1-(11-phenoxyundecyl)-P
2-(2-acetamido-2-deoxy-α-D-galactopyranosyl) diphosphate, which is a synthetic lipid acceptor for glycosyl transferases participating in the biosynthesis
of O-antigenic polysaccharides of Gram-negative bacteria, is suggested. 相似文献
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