[Relict microorganisms of cryolithozone as possible objects of gerontology].

Permafrost is widely distributed in the Northern Hemisphere, and its age reaches hundreds of thousands and millions of years. Permafrost contains alive microorganisms which are not frozen due to relatively high temperature of the environment (-2...-8 degrees C), but the microorganisms are immobilized and therefore aged probably similar to the age of permafrost. Longevity of the relict microbial cells is related obviously to their mechanism of protection against heat, radiation, free radicals and other damaging agents. A strain of Bacillus sp. was isolated from permafrost aged of about 3 million years, 16S rDNA sequence was identified and preliminary testing of bacterial culture on Drosophila melanogaster and mice was made. Immune stimulation and improvement of physical condition were observed, and that, together with the age of the microbial cells, presents the relict microorganisms as objects of gerontology.

[Restriction endonuclease Asi256I recognizing the nucleotide sequence 5'-GATC-3'].

A strain producing a restriction endonuclease was isolated from soil samples and identified as the Arthrobacter sp. strain Ck256. The enzyme produced by this strain was termed Asi2561. The isolation procedure for this enzyme was described, and the optimal conditions for its function were determined. It was shown that the restriction endonuclease Asi256I is a true isoschizomer of MboI, it has a temperature optimum of 6 degrees C, and can be used in molecular-biological and genetic-engineering studies performed at low temperatures.

[The new eubacterium Roseomonas baikalica sp. nov. isolated from core samples collected by deep-hole drilling of the bottom of Lake Baikal].

Microbiological analysis of samples of sedimentary rocks from various eras of the geological history of the Baikal rift has enabled us to isolate a large number of microorganisms that can be classified into new, previously undescribed species. The present work deals with the identification and study of the morphological, biochemical, and physiological properties of one such strain, Che 82, isolated from sample C-29 of 3.4-3.5 Ma-old sedimentary rocks taken at a drilling depth of 146.74 m. As a result of our investigations, strain Che 82 is described as a new bacterial species, Roseomonas baikalica sp. nov., belonging to the genus Roseomonas within the family Methylobacteriaceae, class Alphaproteobacteria.

[Consumption of hydrocarbons by psychrotolerant degrader strains].

Oil-oxidizing microorganisms have been sampled in various regions of Siberia and used in strain associations, which degrade n-alkanes of oil from various fields by 64-92% after 6 days of growth in a wide temperature range. These strains are salt-tolerant and psychrotolerant. They are compatible with aboriginal soil microflora. Promising results have been obtained in experiments on growing plants on oil-polluted soil purified with a biodegrader of this series.

[Genomic and phenotypic analyses of microorganisms isolated from the sediments of Lake Baikal].

Genetic and biochemical methods and morphological examination were used to study microorganisms isolated from samples of deep drilling of the Lake Baikal bottom sediments. Based on blot hybridization patterns, the strains investigated were divided into several groups according to the degree of homology of their genomic DNA. Morphological, biochemical, and ultrastructural characteristics of bacterial strains are described, and their compliance with the genomic analysis data is demonstrated.

[Cultivation of Mycobacterium tuberculosis in cell culture]. / Metod kul'tivirovaniia mikobakterii tuberkuleza na osnove perevivaemoi kul'tury kletok.

The method of the cultivation of M .tuberculosis in cell subcultures was tested. Five consecutive passages of 2 M. tuberculosis strains were carried out with similar inoculation and cultivation conditions. Mycobacterial cells preserved their morphological characteristics in the course of all passages. The method of M. tuberculosis cultivation in subcultured cells made it possible to study of the physiology of M. tuberculosis under conditions, most approximated to the natural tuberculosis infection in humans.

[Entomopathogenic bacteria Bacillus thuringiensis as producers of restriction endonucleases]. / Entomopatogennye bakterii Bacillus thuringiensis--produtsenty éndonukleaz restriktsii.

A total of 115 collection strains of Bacillus thuringiensis, belonging to various subspecies, have been studied for the presence of DNA restriction-modification systems. Restriction endonucleases of 13 strains have been isolated and characterized. No considerable correlations between the taxonomic positions of the bacteria and the specificities of the endonucleases isolated have been detected. It is concluded that the enzymes with identical specificities are present in both the crystalliferous and acrystalliferous strains of the same subspecies.

[Testing and isolation of high-purity restriction endonucleases]. / Testirovanie i vydelenie vysokoochishchennykh éndonukleaz restriktsii.

A new method of testing restriction nucleases is proposed. This method is based on high-temperature treatment of crude cell extracts. Disrupted cells were heated at 50-60 degrees C, centrifuged, and assayed for restrictases. This method provides the opportunity for screening new enzymes in microbial strains enriched with nonspecific restrictases. High-temperature treatment of cell extracts of certain producers reduces the number of steps of the procedure used for isolating high-purity restrictases; the resulting preparations are capable of maintaining high enzymatic activity during long-term storage. It was shown that high-temperature treatment can be applied not only to thermophilic but also to mesophilic strains of microorganisms of different taxa.

[Identification and characterization of strains of Bacillus thuringiensis by genomic fingerprinting using biotinylated phage M13 DNA]. / Identifikatsiia i pasportizatsiia shtammov Bacillus thuringiensis metodom genomnoi daktiloskopii s ispol'zovaniem biotinilirovannoi DNK faga M13]

Genomic DNA of the entomopathogenic bacterium Bacillus thuringiensis was analyzed by the genomic fingerprinting technique. The biotin-labeled single-stranded DNA of the phage M13 was used as a marker of hypervariable sequences. A procedure for analyzing the differentiation among various Bacillus thuringiensis strains was developed. Characteristic patterns of fingerprints were obtained for several strains, the main representatives of subspecies that are most frequently used in the manufacture of bacterial insecticides, such as subsp. thuringiensis, subsp. kurstaki, and subsp. galleriae. Because no essential differences were revealed in band patterns upon comparing fingerprints of crystal-producing bacterial strains with those of acrystallic mutants, it was assumed that the loss of crystal-producing ability in the insect pathogen Bacillus thuringiensis is not connected with significant rearrangement of its genome.

[HpyNI--a novel restriction endonuclease isolated from the pathogenic microorganism Helicobacter pylori]. / HpyNI--pervaia éndonukleaza restriktsii, vydelennaia iz patogennogo mikroorganizma Helicobacter pylori.

HpyNI is the first restriction endonuclease which has been isolated from pathogenic Helicobacter pylori. HpyNI, a new isoschizomer of ScrFI, recognizes and cleaves the palindromic sequence 5'CCNGG-3'.

[Identification and classification of strains of microorganisms using genomic fingerprinting with biotinylated phage M13 DNA]. / Identifikatsiia i pasportizatsiia shtammov mikroorganizmov metodom genomnoi daktiloskopii s ispol'zovaniem biotinilirovannoi DNK faga M13.

To analyze DNA polymorphisms of various bacterial strains, a nonradioactive variant of the genomic fingerprinting method was developed. The method was based on the application of biotin-labeled single-stranded phage M13 DNA as a probe. Characteristic patterns of fingerprints obtained by MvaI, HaeIII, and HinfI restriction enzymes are presented for several species of bacilli and other bacteria. The advantages of this method in microbiology for the identification and characterization of different microbial strains are shown.

[Luminescent bacteria--producers of specific restriction endonucleases]. / Svetiashchiesia bakterii--produtsenty spetsificheskikh éndonukleaz restriktsii.

Luminescent bacteria isolated from the waters of the Black Sea and of the Indian and Pacific Oceans were tested for the presence of restriction endonucleases. For 12 of 19 restriction enzyme producers revealed, restriction sites were determined. The enzymes were identified as isoschizomers of AfIII, BanI, HaeIII, PstI, Sau3AI, and Sau96I. Possible participation of the restriction and modification enzymes in the interaction of bacterial symbionts with the animal macrosymbiont is discussed.

New restriction endonucleases from thermophilic soil bacteria.

Using the most effective rapid method for the detection of restriction endonucleases (ENases) in microorganisms, 32 thermophilic producers have been isolated. All strains belong to the genus Bacillus. Thermostable isoschizomers of ENases, such as AvaI, BbvI, BbvII, BclI, BsaBI, BsiYI, BsrI, BstEII, BstNI, Cfr10I, ClaI, FspI, HaeIII, HpaII, Ksp632I and SfeI, were isolated.

[New type II and IIs restriction endonucleases from thermophilic bacteria of the genus Bacillus]. / Novye éndonukleazy restriktsii tipa II i IIs iz termofil'nykh bakterii roda Bacillus.

Restriction endonucleases have been isolated from 26 strains of thermophilic strains of the Bacillus genus, their recognition sequences were determined, and for 15 of them cleavage sites identified. The enzymes proved to be isoschizomers of known endonucleases BstNI, EarI, HaeIII, HpaII, Cfr10I, BsiYI, BclI, BbvII, BbvI, BstEII, BsaBI, BsrI, FspI, ClaI, SfeI.

[Comparison of a stat method of analysis of microorganisms for the presence of site-specific restriction endonuclease activity]. / Sravnenie ékspress-metodov analiza mikroorganizmov na nalichie aktivnosti sait-spetsificheskikh éndonukleaz restriktsii.

Sensitivity of several express-methods used for detection of bacterial endonucleases was compared. The most sensitive method is that employing Triton X-100.