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91.
92.
The verification of the PREFAB database containing golden standard protein alignments was performed. It has revealed a significant number of differences between the sequences from PREFAB and PDB databases. It was shown that compared to the sequences given in the PDB database 575 alignments refered to a sequence with a gap; such alignments were excluded. Furthermore, compared to the PDB-sequences a single substitute or the insertions were found for 440 aminoacid sequences from PREFAB database; these sequences were edited. SCOP domain analysis has shown that only 502 alignments in the resulting set contain the sequences from the same family. Finally, eliminating duplicates, we have created a new golden standard alignment database PREFAB-P based on PREFAB; the PREFAB-P database contains 581 alignments.  相似文献   
93.
Bird species diversity of the altitudinal belts of the Eastern Himalayas was analyzed in the early spring of 2005 and 2014. Species richness is revealed to be decreasing from the belts of subtropical mixed and coniferous forests to the alpine belt. Specific species that are not beyond the limits of a corresponding belt are immanent to three of four investigated altitudinal belts. The avifaunas of two adjacent belts also have comparatively many common species. One hundred and thirty-three bird species met in both years belong to six faunal complexes, among which most species are Himalayan endemics and subendemics, as well as Palearctic species. The abundance of background species has been determined for each altitudinal belt.  相似文献   
94.
INTRODUCTIONAsearlyasin1948wehavefr8CtionatedisolatednucleifromnormalandtumorcellsbyextractionwithiMNaCIanddilutealkali[1].Thenuclearresiduewasthenstudiedmorethoroughly[2,3].Lateron,sillillarproteinousnuclearresidueswereisolatedbyotherworkers[46]andasstud…  相似文献   
95.
Algorithms and software for support of gene identification experiments   总被引:1,自引:0,他引:1  
MOTIVATION: Gene annotation is the final goal of gene prediction algorithms. However, these algorithms frequently make mistakes and therefore the use of gene predictions for sequence annotation is hardly possible. As a result, biologists are forced to conduct time-consuming gene identification experiments by designing appropriate PCR primers to test cDNA libraries or applying RT-PCR, exon trapping/amplification, or other techniques. This process frequently amounts to 'guessing' PCR primers on top of unreliable gene predictions and frequently leads to wasting of experimental efforts. RESULTS: The present paper proposes a simple and reliable algorithm for experimental gene identification which bypasses the unreliable gene prediction step. Studies of the performance of the algorithm on a sample of human genes indicate that an experimental protocol based on the algorithm's predictions achieves an accurate gene identification with relatively few PCR primers. Predictions of PCR primers may be used for exon amplification in preliminary mutation analysis during an attempt to identify a gene responsible for a disease. We propose a simple approach to find a short region from a genomic sequence that with high probability overlaps with some exon of the gene. The algorithm is enhanced to find one or more segments that are probably contained in the translated region of the gene and can be used as PCR primers to select appropriate clones in cDNA libraries by selective amplification. The algorithm is further extended to locate a set of PCR primers that uniformly cover all translated regions and can be used for RT-PCR and further sequencing of (unknown) mRNA.   相似文献   
96.
It was shown by the example of 1-, 2-, and 4-phenylethynylpyrene 2'-arabino-carbamate derivatives of uridine that the position of pyrene substitution substantially affects the spectral and photophysical properties of the fluorophore and its ability to interact with the nucleic base.  相似文献   
97.
The aim of the work was to develop a PCR-based assay for detection of L. pneumophila and L. micdadei in environmental samples as well as in clinical samples from low respiratory tract and to assess its analytic characteristics. The assay was used during investigation of the outbreak developed in July 2007 in town Verkhnyaya Pyshma (Sverdlovsk region). Polymerase-chain reaction (PCR)with fluorescent detection,sequencing and cloning of DNA fragments were used. Developed assay based on the PCR with fluorescent real-time/ endpointdetection is able to detect L. pneumophila in clinical and environmental samples and to quantify amount of bacterial DNA in water. Specificity of analysis (100%) was assessed using the panel of bacterial strains and samples from healthy individuals. Analytic sensitivity of assay and quantitation limit was 1000 GU in 1 ml. Sensitivity of the assay of artificially contaminated biological samples was 1000 bacteria in 1 ml. During outbreak investigation L. pneumophila DNAwas detected in 4 lung samples from 4 fatal cases, from 1 of 2 sputum samples, 1 of 2 bronchoalveolar lavage samples with X-ray confirmed pneumonia. Legionella's DNA was found in samples from cooling towers, central hot water supply as well as from showerheads in apartments of 3 patients. Fountain and drinking water samples were PCR-negative. Specificity of PCR-positive results was confirmed by sequencing. Use of the assay during outbreak in- vestigation allowed to confirm the diagnosis in fatal cases and quickly identify the possible source of infection.  相似文献   
98.
Glutathione S-transferases (GSTs) comprise a diverse superfamily of enzymes found in organisms from all kingdoms of life. GSTs are involved in diverse processes, notably small-molecule biosynthesis or detoxification, and are frequently also used in protein engineering studies or as biotechnology tools. Here, we report the high-resolution X-ray structure of Atu5508 from the pathogenic soil bacterium Agrobacterium tumefaciens (atGST1). Through use of comparative sequence and structural analysis of the GST superfamily, we identified local sequence and structural signatures, which allowed us to distinguish between different GST classes. This approach enables GST classification based on structure, without requiring additional biochemical or immunological data. Consequently, analysis of the atGST1 crystal structure suggests a new GST class, distinct from previously characterized GSTs, which would make it an attractive target for further biochemical studies.  相似文献   
99.
Tobacco plants (Nicotiana tabacum L.) transformed with the desC gene for acyl-lipid Δ9-desaturase from a thermophilic cyanobacterium Synechococcus vulcanus were cultivated on the agarized Murashige and Skoog medium at 22°C and a 16-h photoperiod. Tobacco plants transformed with an empty binary vector pGA482 served as the control. The investigations showed that, in contrast to the control, transgenic plants maintained a higher activity of antioxidant enzymes during 2-h incubation at 2°C; as a result, these plants resisted more efficiently the accumulation of reactive oxygen species and reduced the rate of the lipid peroxidation. The activity of antioxidant enzymes in the transformed plants is apparently related to the operation of the introduced desC gene for acyl-lipid Δ9-desaturase because the enhanced activity of the latter increased the relative content of polyunsaturated FAs in membrane lipids and in this way promoted the liquid state of membranes during the chilling period. These changes helped preserve the cellular homeostasis and thereby maintain the steady synthesis of antioxidant enzymes at hypothermic conditions; as a result, cold resistance of transformed tobacco plants increased.  相似文献   
100.
Detection of nucleic acid hybridization via fluorescence resonance energy transfer (FRET) using pyren-1-ylmethyl and perylen-3-ylmethyl N2'-functionalized 2'-amino-LNA nucleosides incorporated into oligonucleotides exhibited a clear distance dependence of the FRET efficiency, ranging from below 10% when the fluorophores were approximately 40A apart to approximately 90% when the fluorophores were in close proximity.  相似文献   
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