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91.
Maria del Mar Trigo Baltasar Cabezudo Marta Recio Francisco Javier Toro 《Aerobiologia》1996,12(2):85-90
In the Mediterranean area, Urticaceae pollen, together with the pollen of olive and grasses, are the aeroallergens with the
highest incidence in the population. From October 1991 to September 1993, with the aid of a Burkard spore-trap, we carried
out a study on the Urticaceae pollen content in the atmosphere of Málaga, a seaside resort situated in the Costa del Sol (southern
Spain). In Málaga, the Urticaceae pollen season is very long and their pollen grains are detected throughout the year. However,
peaks were recorded in March and April and the variables most influencing concentration were maximum air temperature, sunshine
hours and relative humidity. Diurnal patterns show that peaks occur generally from 10:00 h to 16:00 h when the temperature
reaches its highest values. 相似文献
92.
93.
Phenylacetyl-Coenzyme A Is the True Inducer of the Phenylacetic Acid Catabolism Pathway in Pseudomonas putida U 总被引:1,自引:1,他引:0
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Beln García Elías R. Olivera Baltasar Miambres David Carnicero Carmen Muiz Germn Naharro Jos M. Luengo 《Applied microbiology》2000,66(10):4575-4578
Aerobic degradation of phenylacetic acid in Pseudomonas putida U is carried out by a central catabolism pathway (phenylacetyl-coenzyme A [CoA] catabolon core). Induction of this route was analyzed by using different mutants specifically designed for this objective. Our results revealed that the true inducer molecule is phenylacetyl-CoA and not other structurally or catabolically related aromatic compounds. 相似文献
94.
Marta Recio Baltasar Cabezudo María del Mar Trigo Francisco Javier Toro 《Aerobiologia》1998,14(2-3):101-107
A pollen calendar has been constructed for Malaga (Southern Spain) based on the data obtained during 5 years (1991–95) using
a Burkard spore trap set up approximately 1 km west of the city. The calendar only reflects taxa which showed a 10-day mean
pollen concentration equal to or greater than 1 grain of pollen/m3 of air. Twenty nine taxa are included, of which the three commonest (Olea europaea, Cupressaceae andQuercus) represent approximately 54% of the total annual count and the following four (Chenopodiaceae-Amaranthaceae, Gramineae, Urticaceae
andPlantago) represent 21.3%. The greatest diversity of pollen types occurs during Spring and the highest concentrations from February
to June, when approximately 85% of the total annual pollen is registered. Several peaks occur during the year principally
due to Cupressaceae in February,Quercus in April,Olea europaea in May andCasuarina in October, although substantial quantities of Urticaceae, Chenopodiaceae-Amaranthaceae,Plantago and Gramineae are also detected in April and May. The pollination of important allergy-producing taxa such as olive and grass
takes place earlier in Malaga than in cities more inland, so that the data presented here may be useful in predicting the
beginning of the pollination season of these localities. 相似文献
95.
Baltasar Escriche Amparo C. Martínez-Ramírez M. Dolores Real Francisco J. Silva Juan Ferr 《Archives of insect biochemistry and physiology》1994,26(4):315-327
The potato tuber moth is susceptible to at least three insecticidal crystal proteins (ICPs) from Bacillus thuringiensis: CrylA(b), CrylB, and CrylC. To design useful combinations of toxin genes either in transgenic plants or in new genetically modified B. thuringiensis strains, it is necessary to determine the binding characteristics of the different ICPs so as not to combine a pair sharing the same binding site. This has been accomplished using two different techniques: 125I-labeling of the ICPs with further measurement of the radioactivity bound to brush border membrane vesicles, and microscopic visualization of the bound ICPs by enzyme-linked reagents such as antibodies or streptavidin using biotinylated ICPs. Our results show that CrylA(b), CrylB, and CrylC bind to different sites in the brush border membrane of midgut epithelial cells. Also, the affinity of the binding sites for the ICPs and their concentration in brush border membrane vesicles has been determined in a laboratory strain and a storage collected population. No significant differences were found between these two strains. © 1994 Wiley-Liss, Inc. 相似文献
96.
Molecular characterization of intrinsic and acquired antibiotic resistance in lactic acid bacteria and bifidobacteria 总被引:1,自引:0,他引:1
Ammor MS Flórez AB van Hoek AH de Los Reyes-Gavilán CG Aarts HJ Margolles A Mayo B 《Journal of molecular microbiology and biotechnology》2008,14(1-3):6-15
The minimum inhibitory concentrations (MICs) of 6 different antibiotics (chloramphenicol, clindamycin, erythromycin, streptomycin, tetracycline and vancomycin) were determined for 143 strains of lactic acid bacteria and bifidobacteria using the Etest. Different MICs were found for different species and strains. Based on the distribution of these MIC values, most of the strains were either susceptible or intrinsically resistant to these antibiotics. However, the MIC range of some of these antibiotics showed a bimodal distribution, which suggested that some of the tested strains possess acquired antibiotic resistance. Screening for resistance genes was performed by PCR using specific primers, or using a DNA microarray with around 300 nucleotide probes representing 7 classes of antibiotic resistance genes. The genes identified encoded resistance to tetracycline [tet(M), tet(W), tet(O) and tet(O/W)], erythromycin and clindamycin [erm(B)] and streptomycin [aph(E) and sat(3)]. Internal portions of some of these determinants were sequenced and found to be identical to genes described in other bacteria. All resistance determinants were located on the bacterial chromosome, except for tet(M), which was identified on plasmids in Lactococcus lactis. The contribution of intrinsic multidrug transporters to the antibiotic resistance was investigated by cloning and measuring the expression of Bifidobacterium breve genes in L. lactis. 相似文献
97.
Santiago-Moreno J Coloma MA Toledano-Díaz A Gómez-Brunet A Pulido-Pastor A Zamora-Soria A Carrizosa JA Urrutia B López-Sebastián A 《Cryobiology》2008,57(1):25-29
Egg yolk-based diluents provide adequate cryoprotection for the sperm of several mammalian species. Traditionally, chicken egg yolk has been used as additive for the freeze preservation of spermatozoa because of its wide availability. Variations in the chemical composition of the egg yolk of different avian species appear to influence the protection afforded during cooling, freezing, and thawing. The aim of the present study was to assess the use of quail egg yolk as a novel additive for the epididymal spermatozoa of a threatened wild ruminant species—the Spanish ibex—and to compare its efficacy with chicken egg yolk. Epididymal spermatozoa were diluted using a Tris–citric acid–glucose medium (TCG) composed of 3.8% Tris (w v−1), 2.2% citric acid (w v−1), 0.6% glucose (w v−1), 5% glycerol (v v−1), and 6% egg yolk (v v−1). Sperm masses from the right epididymes were diluted with TCG-6% chicken egg yolk medium, while those from the left were diluted with TCG-6% quail egg yolk. The thawed spermatozoa preserved with TCG-6% quail egg yolk extender exhibited lower motility (P < 0.001), membrane integrity (P < 0.001), and viability (P < 0.01) than those diluted with the TCG-6% chicken egg yolk extender. The fertility of spermatozoa frozen in TCG-6% chicken egg yolk tended to be higher than in those frozen with TCG-6% quail egg yolk (63.3% vs 36.4%, P = 0.19). These results show that quail egg yolk offers no advantages over chicken egg yolk in the cryopreservation of Spanish ibex epididymal spermatozoa. 相似文献
98.
Two Different Tetracycline Resistance Mechanisms, Plasmid-Carried tet(L) and Chromosomally Located Transposon-Associated tet(M), Coexist in Lactobacillus sakei Rits 9
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Mohammed Salim Ammor Miguel Gueimonde Morten Danielsen Monique Zagorec Angela H. A. M. van Hoek Clara G. de los Reyes-Gaviln Baltasar Mayo Abelardo Margolles 《Applied microbiology》2008,74(5):1394-1401
Lactobacillus sakei is extensively used as functional starter culture in fermented meat products. One of the safety criteria of a starter culture is the absence of potentially transferable antibiotic resistance determinants. However, tetracycline-resistant L. sakei strains have already been observed. In this paper, we show that tetracycline resistance in L. sakei Rits 9, a strain isolated from Italian Sola cheese made from raw milk, is mediated by a transposon-associated tet(M) gene coding for a ribosomal protection protein and a plasmid-carried tet(L) gene coding for a tetracycline efflux pump. pLS55, the 5-kb plasmid carrying the tet(L) gene, is highly similar to the pMA67 plasmid recently described for Paenibacillus larvae, a species pathogenic to honeybees. pLS55 could be transferred by electroporation into the laboratory strain L. sakei 23K. While the L. sakei 23K transformant containing pLS55 displayed an intermediate tetracycline resistance level (MIC, <32 μg/ml), L. sakei Rits 9, containing both tetracycline-resistant determinants, had a MIC of <256 μg/ml, suggesting that Tet L and Tet M confer different levels of resistance in L. sakei. Remarkably, in the absence of tetracycline, a basal expression of both genes was detected for L. sakei Rits 9. In addition, subinhibitory concentrations of tetracycline affected the expression patterns of tet(M) and tet(L) in different ways: the expression of tet(M) was induced only at high tetracycline concentrations, whereas the expression of tet(L) was up-regulated at lower concentrations. This is the first time that two different mechanisms conferring resistance to tetracycline are characterized for the same strain of a lactic acid bacterium. 相似文献
99.
This paper reports the construction of several general cloning vectors and a specialized depurative vector based on a new lactococcal plasmid that replicates by the rolling circle mechanism [pBM02; Plasmid 49 (2003) 118]. Most vectors are shuttle vectors for Escherichia coli-Lactococcus lactis and carry replicons of both ColE1 and pBM02 plasmids (ColE1 is used even though the pBM02 replicon is fully active in both Gram-positive and Gram-negative organisms). Segregational and structural studies indicated that the new vectors were stable enough for the majority of applications. Further, since the basic replicon is compatible with plasmid derivatives of pWV01 and pSH71, they can be maintained in the same cell with members of the two largest vector series for L. lactis and other lactic acid bacteria, the pGK, and the pNZ series. 相似文献
100.
A strong correlation between two mannose phosphate isomerase (MPI) isoenzymes and resistance to Cry1A toxins from Bacillus thuringiensis has been found in a Plutella xylostella population. MPI linkage to Cry1A resistance had previously been reported for a Heliothis virescens population. The fact that the two populations share similar biochemical, genetic, and cross-resistance profiles of resistance suggests the occurrence of homologous resistance loci in both species. 相似文献