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991.
992.
A direct correlation has been established between pink-colored pigmentation and the production of insecticide crystals (toxins) for some Bacillus thuringiensis (BT) pigmented cultures. This regularity was for the first time determined by us for BT strains of the H3, H10, and H16 serotype. Pigment-free clones of these serotypes do not produce crystals. A correlation was not observed in the case of H14 serotype strains with oval inclusions. The revealed correlation makes it possible to distinguish crystal-yielding colonies in cultures of the above-mentioned serotypes by the availability of pigmentation. This method can serve as an effective express method for the detection of virulent clones, which is especially important if these strains are used for obtaining insecticide preparations.  相似文献   
993.
The strain Fusarium sp. no. 56 isolated from natural oil-containing soil samples taken near the city of Oktyabr'skii, Republic of Bashkortostan, displayed a pronounced capability of biotransforming oil and its light and heavy fractions. This micromycete is nonpathogenic and can grow at 5–10°C. The latter property is of practical significance for its uses in soil and water bioremediation under the cold climatic conditions of Bashkortostan and other regions.  相似文献   
994.
MatK and rbcL are recommended as the official barcode loci for higher plants but there remains a need for additional universal markers. We generated a series of 84 new universal primers targeting 42 plastid loci that all yielded single amplicons when applied to DNA templates from 19 diverse higher plant families. Marker utility ultimately depends on sequence variability, with rapidly evolving loci being useful for barcoding or biogeographic applications and more conserved loci being better suited to deep phylogeny reconstruction. Whereas excessive size variation is undesirable for many applications, modest size variability caused by indels and the sequence variation frequently associated with indels are highly desirable. We therefore performed a quick screen of the markers for size and sequence variation using pooled DNA templates from 96 taxonomically diverse species. All markers produced little or no size variation (consistent with the presence of minor indels). The seven regions exhibiting most size variation in pooled templates (rpl23&rpl2.1, 16S, 23S, 4.5S&5S, petB&D and rpl2, rpoC1 and trnK introns) were then amplified for all species individually, confirming the pooled template results. When the most variable loci (introns of trnK and rpoC1) were sequenced for all 96 species, a high level of sequence variation (nucleotide substitutions and indels) was observed among congeneric species groups for both loci. Both markers therefore have potential as supplementary barcode markers.  相似文献   
995.
996.
997.
A model of formation of radiation-induced cytogenetic damage is proposed on the basis of our own and literature data. The model postulates that localization of DNA damage and repair process play an important role in the final effect.  相似文献   
998.
999.
An enlarged threshold model of the Regulatory System of Development of λ -Phage (RSDP λ-2) is built. It includes 15 synthetic blocks of proteins and mRNAs and four blocks corresponding to the other ontogenetic processes: two-stage replication, integration and excision of phage genome, formation of oligomers of regulatory proteins, regulation of bacteriallysis. By way of computer simulation of the RSDP A-2 model the dynamics of concentrations of all main proteins, respective fractions of mRNAs and DNA are described in the lytic and lysogenic regimes of phage ontogenesis. Results obtained are in good agreement with available experimental data. The dependence of a portion (%) of lysogenic responses on the multiplicity k of phage infection of bacterial culture, is built. This curve has a maximum point in accordance with the experimental data of P. Kourilsky (1973).  相似文献   
1000.
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