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1.
The radioactive precursor, [3-3H]oleanolic acid was administrated to excised roots from four weeks old Calendula officinalis L. plants. Transformations of this compound into two series of its glycosides, i.e. glucosides and glucuronides were investigated. For the first time it has been shown that both series of oleanolic acid glycosides
are synthesized in roots of young marigold plants. The pathway of their biosynthesis seems to be similar, although not identical,
to the pathway occurring in green organs of C. officinalis. 相似文献
2.
Kukulj S Mehulić M Barisić B Kamauf-Balabanić B Krizanac S 《Collegium antropologicum》2004,28(2):931-936
A case is presented of pulmonary botryomycosis in a 61-year-old man with a massive right-side pulmonary infiltrate which looked like a tumor (on X-ray). Microscopic examination of a transbronchial biopsy specimen revealed chronic suppurative inflammation, which did not regress despite intensive antibiotic therapy for a period of two months. Histological analysis of specimens taken during surgery for hemoptysis revealed pulmonary botryomycosis. The disease was diagnosed on the basis of characteristic eosinophilic granules in which the bacteria are surrounded by protein material (Splendore-Hoeppli phenomenon). Pulmonary actinomycosis was excluded. The case demonstrates that pulmonary botryomycosis can have the appearance of a mass which resembles pulmonary carcinoma on X-ray, and may also be mistaken for pulmonary actinomycosis. For this reason, pulmonary botryomycosis, although rare, should be excluded during differential diagnosis of hemoptysis or pulmonary infiltrates. 相似文献
3.
Alicia Alonso-Hernando Rosa Capita Miguel Prieto Carlos Alonso-Calleja 《Journal of microbiology (Seoul, Korea)》2009,47(2):142-146
Information on the potential for acquired reduced susceptibility of bacteria to poultry decontaminants occurring is lacking.
Minimal Inhibitory Concentrations (MICs) were established for assessing the initial susceptibility and the adaptative and
cross-adaptative responses of four bacterial strains (Listeria monocytogenes serovar l/2a, L. monocytogenes serovar 4b, Salmonella enterica serotype Typhimurium, and S. enterica serotype Enteritidis) to four poultry decontaminants (trisodium phosphate, acidified sodium chlorite -ASC-, citric acid,
and peroxyacetic acid). The initial susceptibility was observed to differ among species (all decontaminants) and between Salmonella strains (ASC). These inter- and intra-specific variations highlight (1) the need for strict monitoring of decontaminant concentrations
to inactivate all target pathogens of concern, and (2) the importance of selecting adequate test strains in decontamination
studies. MICs of ASC (0.17±0.02 to 0.21±0.02 mg/ml) were higher than the U.S. authorized concentration when applied as a pre-chiller
or chiller solution (0.05 to 0.15 mg/ml). Progressively increasing decontaminant concentrations resulted in reduced susceptibility
of strains. The highest increase in MIC was 1.88 to 2.71-fold (ASC). All decontaminants were shown to cause cross-adaptation
of strains between both related and unrelated compounds, the highest increase in MIC being 1.82-fold (ASC). Our results suggest
that the in-use concentrations of ASC could, in certain conditions, be ineffective against Listeria and Salmonella strains. The adaptative and cross-adaptative responses of strains tested to poultry decontaminants are of minor concern.
However, the observations being presented here are based on in vitro studies, and further research into practical applications are needed in order to confirm these findings. 相似文献
4.
Garbayo I Vílchez C Vega JM Nava-Saucedo JE Barbotin JN 《Biotechnology letters》2004,26(23):1825-1827
Streptococcus thermophilusand Lactobacillus bulgaricus were co-immobilized in different systems with varying calcium (0.1–1.5M) and alginate (1–2<><>, w/v) concentrations. Highest lactic acid production was 35 g l1 when both bacteria were in high viscosity beads (1<><>, w/v alginate) hardened in 0.1 M CaCl2 .The gel bead composition affected size and distribution of entrapped lactic acid bacteria. 相似文献
5.
The cellular fatty acid composition of 14 strains of Caulobacter species and types, two species of Prosthecomicrobium, and two species of Asticcacaulis was determined by gas-liquid chromatography. In most of these bacteria, the major fatty acids were octadecenoic acid (C18:1), hexadecenoic acid (C16:1) and hexadecanoic acid (C16:0). Some cyclopropane and branched chain fatty acids were detected in addition to the straight chained acids. Hydroxytetradecanoic acid was an important component of P. enhydrum but significant amounts of hydroxy acids were not detected in other prosthecate bacteria examined.Abbreviations DEGS
diethylene glycol succinate
- A
measare of association
Dedicated to Prof. R. Y. Stanier on the occasion of his 60th birthday 相似文献
6.
During a 2½-year period, in a 360-bed general hospital, three cases of pulmonary actinomycosis were encountered in men aged 38, 47 and 49 years. In each instance the symptoms, signs and radiological and laboratory findings were such as to warrant a presumptive clinical diagnosis of bronchogenic carcinoma. Thoracotomy was performed in each case. This experience suggests that a definitive clinical diagnosis of bronchogenic carcinoma should not be made without histological evidence. Furthermore, such individuals should have the benefit of exploratory thoracotomy on the off-chance that the pulmonary lesion may be benign and amenable to treatment. Above all it should be remembered that pulmonary actinomycosis can simulate bronchogenic carcinoma to a marked degree. 相似文献
7.
Erik Eschbach Martin Pfannkuchen Michael Schweikert Denja Drutschmann Franz Brümmer Sergei Fokin Wolfgang Ludwig Hans-Dieter Grtz 《Systematic and applied microbiology》2009,32(7):490-500
An intracellular bacterium was discovered in two isolates of Paramecium sexaurelia from an aquarium with tropical fish in Münster (Germany) and from a pond in the Wilhelma zoological–botanical garden, Stuttgart (Germany). The bacteria were regularly observed in the cytoplasm of the host, but on some occasions they were found in the macronucleus of the host cell. In these cases, only a few, if any, bacteria were observed remaining in the cytoplasm. The bacterium was not infectious to P. sexaurelia or other species of Paramecium and appeared to be an obligate intracellular bacterium, while bacteria-free host cells were completely viable. The fluorescence in situ hybridisation (FISH) and comparative 16SrDNA sequence analyses showed that the bacterium belonged to a new genus, and was most closely, yet quite distantly, related to Holospora obtusa. In spite of this relationship, the new bacteria differed from Holospora by at least two biological features. Whereas all Holospora species reside exclusively in the nuclei of various species of Paramecium and show a life cycle with a morphologically distinct infectious form, for the new bacterium no infectious form and no life cycle have been observed. For the new bacterium, the name Candidatus Paraholospora nucleivisitans is suggested. The host P. sexaurelia is usually known from tropical and subtropical areas and is not a species typically found in Germany and central Europe. Possibly, it had been taken to Germany with fish or plants from tropical or subtropical waters. Candidatus Paraholospora nucleivisitans may therefore be regarded as an intracellular neobacterium for Germany. 相似文献
8.
Ronghua Qian Zhaohua Xiao Chongwen Zhang Wuying Chu Zhijuan Mao Lian Yu 《World journal of microbiology & biotechnology》2008,24(2):245-251
Vibrio alginolyticus, a Gram-negative bacterium, is one of Vibrio pathogens common to human and marine animals. Outer membrane proteins of bacteria play an important role during infection
and induction of host immune response. In present research, two outer membrane protein genes (OmpK and OmpW) of V. alginolyticus were cloned and expressed. The open reading frames of OmpK and OmpW contain 846 bp and 645 bp, respectively, the mature proteins consist of 261 and 193 amino acid residues. At the signal peptides
positions −3 to −1, the amino acids were V-M-A in OmpK and V-F-A in OmpW, which consistented with the observed sequence V-X-A of the signal peptides of transmembrane OMP. The alignment analysis
indicated that both proteins were highly conserved, which could serve as surface antigens for vaccine candidates. SDS-PAGE
indicated two genes over-expressed in E. coli BL21 (DE3). By affinity chromatography on Ni2+-nitriloaceate resin, the recombinant proteins were purified from inclusion bodies. Western blot analysis revealed that both
proteins had immunoreactivity, which provided a base for further study on the evaluation of diagnostication and vaccine candidates. 相似文献
9.
We investigated seasonal variations in allelopathic potential ofArtemisia princeps var.orientalis. Aqueous and meth-anol extracts and volatile substances were prepared in the laboratory from samples collected monthly (April
through October). Their impacts were then assessed on the germination and seedling growth ofLactuca sativa andAchyranthes japonica. The allelopathic potential varied with the time of sample collection and the concentration tested. For example, germination
ofL. sativa was not inhibited by the aqueous extract but seedling growth (shoots and roots) was, with its seasonal effect being significant.
ForA. japonica, seed germination was not inhibited at lower concentrations (except for August samples). However, at higher concentrations
and in certain months (especially July), germination was more negatively affected. The degree of seedling growth inhibition
also differed by month and by extract concentration, with roots being impacted more than shoots. Volatile substances also
had a time-dependent influence on the germination and seedling elongation ofA. japonica. In a separate experiment, the ethyl-acetate and water fractions of a crude methanol extract were prepared monthly fromA. princeps var.orientalis. Here, we examined their antimicrobial activities against three gram-positive bacteria (Bacillus cereus, Bacillus subtilis, andStaphylococcus aureus), two gramnegative bacteria (Escherichia coli andPseudomonas fluorescens), and one lactic acid bacterium,Lactobacillus plantar urn. The ethyl-acetate fraction that was sampled in September was remarkably potent againstB. cereus andB. subtilis, whereas the water fraction collected in August and September showed great antimicrobial activity against the grampositive
and -negative bacteria. In contrast,L. plantarum was not inhibited by the water fraction, regardless of the sampling month. Likewise, the ethyl-acetate and water fractions
collected in April and October had the lowest levels of antimicrobial activity. 相似文献
10.
Christen JM Campbell JF Zurek L Shapiro-Ilan DI Lewis EE Ramaswamy SB 《Journal of invertebrate pathology》2008,99(1):35-42
Entomopathogenic nematodes of the family Steinernematidae and their mutualistic bacteria (Xenorhabdus spp.) are lethal endoparasites of insects. We hypothesized that growth of the nematode’s mutualistic bacteria in the insect host may contribute to the production of cues used by the infective juveniles (IJs) in responding to potential hosts for infection. Specifically, we tested if patterns of bacterial growth could explain differences in CO2 production over the course of host infection. Growth of Xenorhabdus cabanillasii isolated from Steinernema riobrave exhibited the characteristic exponential and stationary growth phases. Other non-nematode symbiotic bacteria were also found in infected hosts and exhibited similar growth patterns to X. cabanillasii. Galleria mellonella larvae infected with S. riobrave produced two distinct peaks of CO2 occurring at 25.6–36 h and 105–161 h post-infection, whereas larvae injected with X. cabanillasii alone showed only one peak of CO2, occurring at 22.8–36.2 h post-injection. Tenebrio molitor larvae infected with S. riobrave or injected with bacteria alone exhibited only one peak of CO2 production, which occurred later during S. riobrave infection (41.4–64.4 h post-infection compared to 20.4–35.9 h post-injection). These results indicate a relationship between bacterial growth and the first peak of CO2 in both host species, but not for the second peak exhibited in G. mellonella. 相似文献
11.
Pepi M Heipieper HJ Fischer J Ruta M Volterrani M Focardi SE 《Extremophiles : life under extreme conditions》2008,12(3):343-349
Bacillus sp. ORAs2 and Pseudomonas sp. ORAs5, two arsenic-resistant bacterial strains previously isolated from sediments of the Orbetello Lagoon, Italy, were
tested for their adaptation to mixed contaminants on the level of membrane fatty acid composition. The two bacterial strains
were characterized by high levels of arsenic resistance, and Pseudomonas sp. ORAs5 was also shown to be solvent-tolerant. The bacterial strains were exposed to mixtures of two toxic compounds: arsenic
at fixed concentrations and toluene in variable amounts or, alternatively, toluene at constant values along with arsenic added
at variable concentrations. Both strains react to the contaminants by changing the composition of their membrane fatty acids.
Bacillus sp. strain ORAs2 showed a correlation between growth rate decreases and fatty acids degree of saturation increases in both
cases, although pointedly in the presence of 1, 2, and 3 mM of toluene and different additions of arsenic, counteracting membranes
fluidity induced by toxic compounds. In Pseudomonas sp. ORAs5, adaptive changes in membrane composition was observed both in terms of increases in the degree of saturation and
in the trans/cis ratio of unsaturated fatty acids in the presence of varying toluene and constant arsenic concentrations, whereas only minor
changes occurred with increasing arsenic and constant toluene concentrations. Thus, on the level of membrane composition,
Bacillus sp. ORAs2 showed a higher potential for adaptation to the presence of mixed pollutants, suggesting its probable suitability
for bioremediation purposes. 相似文献
12.
Lactic acid bacteria (LAB) are important members of the human vaginal microbiota and their presence is considered beneficial.
However, little is known about native vaginal bacteria in other animal species such as the horse. The aim of this work was
to quantify the vaginal lactic acid bacteria and lactobacilli of mares and to establish if selected equine vaginal lactic
acid bacteria, particularly Lactobacillus and Enterococcus spp. strains, could exhibit potential as probiotics. The vaginal lactic acid bacteria and lactobacilli of 26 mares were quantified
by plate counts. Five strains (three Lactobacillus spp. and two Enterococcus spp.) were characterised and adhesion to vaginal epithelial cells, antimicrobial activity and ability to form biofilms were
evaluated. Lactic acid bacteria were recovered from the 26 samples and lactobacilli counts were detected in 18 out of 26 mares
(69%). Probiotic properties tested in this study varied among the isolates and showed promising features for their use as
equine probiotics. 相似文献
13.
Loeffler M Le'Negrate G Krajewska M Reed JC 《Cancer immunology, immunotherapy : CII》2009,58(5):769-775
Intravenously-applied bacteria tend to accumulate in tumors and can sporadically lead to tumor regression. Systemic administration
of attenuated Salmonella typhimurium is safe and has shown no significant adverse effects in humans. The purpose of this study was to test the hypothesis that
engineering S. typhimurium to express a chemokine, CCL21, would increase anti-tumor activity. We engineered an attenuated strain of S. typhimurium to produce the chemokine CCL21. Attenuated S. typhimurium expressing CCL21 significantly inhibited the growth of primary tumors and pulmonary metastases in preclinical models of multi-drug-resistant
murine carcinomas, while control bacteria did not. Histological analysis of tumors showed marked inflammatory cell infiltrates
in mice treated with CCL21-expressing but not control bacteria. Levels of cytokines and chemokines known to be induced by
CCL21 [e.g., interferon-γ (INFγ), CXCL9, and CXCL10] were significantly elevated in tumors of mice treated with CCL21-expressing
but not control S. typhimurium. The anti-tumor activity was found to be dependent on CD4- and CD8-expressing cells, based on antibody-mediated in vivo immuno-depletion
experiments. Anti-tumor activity was achieved without evidence of toxicity. In summary, chemokine-expressing, attenuated bacteria
may provide a novel approach to cancer immunotherapy for effective and well-tolerated in vivo delivery of immunomodulatory
proteins.
Markus Loeffler and John C. Reed should be considered senior authors. 相似文献
14.
Tao Zhang Lei Li Xiao-fen Wang Zhao-hai Zeng Yue-gao Hu Zong-jun Cui 《World journal of microbiology & biotechnology》2009,25(6):965-971
Silages are important feedstuffs. Homofermentative lactic acid bacterial inoculants are often used to control silage fermentation.
However, some research pointed out those homofermentative lactic acid bacteria (LAB) impaired the aerobic stability of wheat,
sorghum, and corn silages. Adding heterofermentative LAB can produce more acetic acid, thereby stabilizing silages during
aerobic exposure. Alfalfa is difficult to ensile. The present work was to study the effects of L. buchneri (heterofermentative LAB), alone or in combination with L. plantarum (homofermentative LAB) on the fermentation, aerobic stability, bacteria diversity and ruminal degradability of alfalfa silage.
After 90 days ensiling, the pH, NH3-N/TN, butyric acid content and molds counts of control were the highest. The inoculated silages had more lactic acid, acetic
acid content and more lactic acid bacteria than the control. Inoculating LAB inhibited harmful microorganisms, such as Enterobacterium and Klebsiella pneumoniae. The L. buchneri + L. plantarum-inoculated silage had more acetic acid and less yeasts than other three treatments (P < 0.05), and lower NH3-N/TN than control (P < 0.05). The CO2 production of L. buchneri + L. plantarum-inoculated silage was less than that of L. plantarum-inoculated silage (P < 0.05). Inoculating LAB in alfalfa silages can decrease pH, increase the production of lactic and acetic acids, reduce the
number of yeasts and molds, and inhibit Enterobacterium and K. pneumoniae. Inoculating with L. buchneri or L. buchneri + L. plantarum can improve aerobic stability of alfalfa silages. A combination of L. buchneri and L. plantarum is preferable because it enhanced alfalfa silage quality and aerobic stability. 相似文献
15.
An ABC transporter gene from Clostridium hathewayi is characterized. It has duplicated ATPase domains in addition to a transmembrane protein. Its deduced amino acid sequence
has conserved functional domains with ATPase components of the multidrug efflux pump genes of several bacteria. Cloning this
transporter gene into C. perfringens and E. coli resulted in decreased sensitivities of these bacteria to fluoroquinolones. It also decreased the accumulation and increased
the efflux of ethidium bromide from cells containing the cloned gene. Carbonyl cyanide-m-chlorophenylhydrazone (CCCP) inhibited both accumulation and efflux of ethidium bromide from these cells. The ATPase mRNA
was overexpressed in the fluoroquinolone-resistant strain when exposed to ciprofloxacin. This is the first report of an ABC
transporter in C. hathewayi.
An erratum to this article can be found at 相似文献
16.
Launen LA Dutta J Turpeinen R Eastep ME Dorn R Buggs VH Leonard JW Häggblom MM 《Biodegradation》2008,19(3):347-363
The aerobic polyaromatic hydrocarbon (PAH) degrading microbial communities of two petroleum-impacted Spartina-dominated salt marshes in the New York/New Jersey Harbor were examined using a combination of microbiological, molecular
and chemical techniques. Microbial isolation studies resulted in the identification of 48 aromatic hydrocarbon-degrading bacterial
strains from both vegetated and non-vegetated marsh sediments. The majority of the isolates were from the genera Paenibacillus and Pseudomonas. Radiotracer studies using 14C-phenanthrene and 14C-pyrene were used to measure the PAH-mineralization activity in salt marsh sediments. The results suggested a trend towards
increased PAH mineralization in vegetated sediments relative to non-vegetated sediments. This trend was supported by the enumeration
of PAH-degrading bacteria in non-vegetated and vegetated sediment using a Most Probable Numbers (MPN) technique, which demonstrated
that PAH-degrading bacteria existed in non-vegetated and vegetated sediments at levels ranging from 102 to 105 cells/g sediment respectively. No difference between microbial communities present in vegetated versus non-vegetated sediments
was found using terminal restriction fragment length polymorphism (of the 16S rRNA gene) or phospholipid fatty acid analysis.
These studies provide information on the specific members and activity of the PAH-degrading aerobic bacterial communities
present in Spartina-dominated salt marshes in the New York/New Jersey Harbor estuary. 相似文献
17.
One solution to the global crisis of antibiotic resistance is the discovery of novel antimicrobial compounds for clinical
application. Marine organisms are an attractive and, as yet, relatively untapped resource of new natural products. Cell extracts
from the marine diatom, Phaeodactylum tricornutum, have antibacterial activity and the fatty acid, eicosapentaenoic acid (EPA), has been identified as one compound responsible
for this activity. During the isolation of EPA, it became apparent that the extracts contained further antibacterial compounds.
The present study was undertaken to isolate these additional antibacterial factors using silica column chromatography and
reverse-phase high-performance liquid chromatography. Two antibacterial fractions, each containing a pure compound, were isolated
and their chemical structures were investigated by mass spectrometry and nuclear magnetic resonance spectroscopy. The antibacterial
compounds were identified as the monounsaturated fatty acid (9Z)-hexadecenoic acid (palmitoleic acid; C16:1 n-7) and the relatively unusual polyunsaturated fatty acid (6Z, 9Z, 12Z)-hexadecatrienoic acid (HTA; C16:3 n-4). Both are active against Gram-positive bacteria with HTA further inhibitory to the
growth of the Gram-negative marine pathogen, Listonella anguillarum. Palmitoleic acid is active at micro-molar concentrations, kills bacteria rapidly, and is highly active against multidrug-resistant
Staphylococcus aureus. These free fatty acids warrant further investigation as a new potential therapy for drug-resistant infections. 相似文献
18.
A lytic enzyme cocktail from <Emphasis Type="Italic">Streptomyces</Emphasis> sp. B578 for the control of lactic and acetic acid bacteria in wine 总被引:1,自引:0,他引:1
V. Blättel K. Wirth H. Claus B. Schlott P. Pfeiffer H. König 《Applied microbiology and biotechnology》2009,83(5):839-848
Beside yeasts, lactic acid bacteria (LAB) are the most abundant microbes in must during vinification. Whereas Oenococcos oeni is commercially used as a starter culture for the biological acid reduction in wines, other species are responsible for different
types of wine spoilage. Members of the genera Pediococcus, Weissella, Leuconostoc, and Lactobacillus are producers of exopolysaccharide slimes, biogenic amines, acetic acid, and other off-flavors. In order to control microbial
growth, different procedures such as heating of must and addition of sulfite or lysozyme from egg white are generally applied.
Yet, because of health risks, the application of sulfite should be reduced and lysozyme is not effective against all LAB.
In this study, we describe exoenzymes from a Streptomyces sp. strain B578 lysing nearly all wine-relevant strains of LAB and Gram-negative acetic acid bacteria. The lytic enzymes
were active under wine-making conditions, such as the presence of sulfite and ethanol, low temperatures, and low pH values.
The analysis of the exoenzyme composition revealed a synergistic action of different cell wall hydrolases. In conclusion,
the lytic cocktail of Streptomyces sp. B578 is a promising tool for the control of wine-spoiling bacteria.
This article is dedicated to Prof. Dr. Ferdinand Radler on the occasion of his 80th birthday. 相似文献
19.
This study investigates the effects of bacteria occurring in thecytoplasm of some arbuscular mycorrhizal fungi (AMF) on their symbioticefficiency. Gigaspora margarita, Gigasporarosea and Glomus versiforme, containing orwithout intracellular bacteria, were compared for their efficiency instimulating growth of Lactuca sativa L. Biomass productionand nutrient contents were evaluated in plants grown on two substrates. Theefficiency of G. margarita harbouring a homogenouspopulation of Burkholderia was greater than that of theother two AMF, mainly G. rosea, which does not containintracellular bacteria. When plants were grown in poor soil, inoculation withG. margarita resulted in the best growth rates as well asthe highest N, P and K values. The significantly higher N content is ofparticular importance, since the genome of Burkholderiapossesses nif genes. 相似文献
20.
Shu-Hua Qi Ying Xu Hai-Rong Xiong Pei-Yuan Qian Si Zhang 《World journal of microbiology & biotechnology》2009,25(3):399-406
To investigate the antifouling secondary metabolites from marine-derived fungi, we used bioassay-guided column chromatography
techniques, such as HPLC, to separate and purify compounds from Cladosporium sp. F14. Extensive spectral analyses including 1D NMR spectra and MS were employed for structure elucidation of the compounds.
Antilarval activity of the compounds was evaluated in settlement inhibition assays with laboratory-reared Balanus amphitrite and Bugula neritina larvae, while antibacterial activity was assessed with disc diffusion bioassay on growth inhibition of six marine bacterial
species. In total, nine compounds were obtained. Among them, 3-phenyl-2-propenoic acid, cyclo-(Phe-Pro) and cyclo-(Val-Pro)
had various antibacterial activities against three fouling bacteria, furthermore, 3-phenyl-2-propenoic acid and bis(2-ethylhexyl)phthalate
effectively inhibited larval settlement of B. neritina and B. amphitrite larvae, respectively, indicating that the two compounds are potential natural antifouling agents. 相似文献