Publications by authors named "Kozyavkin S"

Bacteriophage AR9 and its close relative PBS1 have been extensively used to construct early Bacillus subtilis genetic maps. Here, we present the 251,042bp AR9 genome, a linear, terminally redundant double-stranded DNA containing deoxyuridine instead of thymine. Multiple AR9 genes are interrupted by non-coding sequences or sequences encoding putative endonucleases.

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A standard draft genome sequence of the white rot saprotrophic fungus Trametes hirsuta 072 (Basidiomycota, Polyporales) is presented. The genome sequence contains about 33.6 Mb assembled in 141 scaffolds with a G+C content of ~57.

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A new Lactobacillus acidophilus strain, FSI4, isolated from yogurt, was isolated and sequenced in our laboratory. Our data, although supportive of previous conclusions regarding the remarkable stability of L. acidophilus species, indicate accumulating mutations in commercial L.

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We have previously introduced a general kinetic approach for comparative study of processivity, thermostability, and resistance to inhibitors of DNA polymerases [Pavlov, A. R., et al.

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Vegetable fermentations rely on the proper succession of a variety of lactic acid bacteria (LAB). Leuconostoc mesenteroides initiates fermentation. As fermentation proceeds, L.

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Background: Bifidobacteria are frequently proposed to be associated with good intestinal health primarily because of their overriding dominance in the feces of breast fed infants. However, clinical feeding studies with exogenous bifidobacteria show they don't remain in the intestine, suggesting they may lose competitive fitness when grown outside the gut.

Results: To further the understanding of genetic attenuation that may be occurring in bifidobacteria cultures, we obtained the complete genome sequence of an intestinal isolate, Bifidobacterium longum DJO10A that was minimally cultured in the laboratory, and compared it to that of a culture collection strain, B.

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The genomes of two closely related lytic Thermus thermophilus siphoviruses with exceptionally long (approximately 800 nm) tails, bacteriophages P23-45 and P74-26, were sequenced completely. The P23-45 genome consists of 84,201 bp with 117 putative open reading frames (ORFs), and the P74-26 genome has 83,319 bp and 116 putative ORFs. The two genomes are 92% identical with 113 ORFs shared.

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Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacteria encode a broad repertoire of transporters for efficient carbon and nitrogen acquisition from the nutritionally rich environments they inhabit and reflect a limited range of biosynthetic capabilities that indicate both prototrophic and auxotrophic strains.

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We determined the sequence of the 152,372 bp genome of phiYS40, a lytic tailed bacteriophage of Thermus thermophilus. The genome contains 170 putative open reading frames and three tRNA genes. Functions for 25% of phiYS40 gene products were predicted on the basis of similarity to proteins of known function from diverse phages and bacteria.

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Fimers are specifically modified primers selected to inhibit nonspecific interactions occurring in cycle sequencing. They are postsynthetically derived from 2'-methoxyoxalamido or 2'-succinimido precursor oligonucleotides by treatment with appropriate small molecular weight modifiers (a primary aliphatic amine or hydroxide anion). We describe design, synthesis, and purification of fimers, and their use in protocols for direct sequencing of genomic deoxyribonucleic acid (DNA).

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Helix-hairpin-helix (HhH) is a widespread motif involved in sequence-nonspecific DNA binding. The majority of HhH motifs function as DNA-binding modules with typical occurrence of one HhH motif or one or two (HhH)(2) domains in proteins. We recently identified 24 HhH motifs in DNA topoisomerase V (Topo V).

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We have determined the complete 1,694,969-nt sequence of the GC-rich genome of Methanopyrus kandleri by using a whole direct genome sequencing approach. This approach is based on unlinking of genomic DNA with the ThermoFidelase version of M. kandleri topoisomerase V and cycle sequencing directed by 2'-modified oligonucleotides (Fimers).

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Synthesis of 2'-modified oligonucleotides from 2'-methoxyoxalamido (MOX) and 2'-succinimido (SUC) precursors is described. Their physical and biochemical properties were assessed. Synthesized oligonucleotides were used as primers in advanced DNA sequencing protocols.

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Previously we have characterized type IB DNA topoisomerase V (topo V) in the hyperthermophile Methanopyrus kandleri. The enzyme has a powerful topoisomerase activity and is abundant in M. kandleri.

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Selenium has been implicated in cancer prevention, but the mechanism and possible involvement of selenoproteins in this process are not understood. To elucidate whether the 15-kDa selenoprotein may play a role in cancer etiology, the complete sequence of the human 15-kDa protein gene was determined, and various characteristics associated with expression of the protein were examined in normal and malignant cells and tissues. The 51-kilobase pair gene for the 15-kDa selenoprotein consisted of five exons and four introns and was localized on chromosome 1p31, a genetic locus commonly mutated or deleted in human cancers.

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Histones have been identified recently in many prokaryotes. These histones, unlike their eukaryotic homologs, are of a single uniform type that is thought to resemble the archetypal ancestor of the eukaryotic histone family. In this paper we report the finding, the cloning and the phylogenetic analysis of the sequence of a prokaryotic histone from the hyperthermophile Methanopyrus kandleri .

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A recently described reverse gyrase from the hyperthermophilic methanogen Methanopyrus kandleri is the only known example of a heterodimeric type I topoisomerase. The enzyme is made up of a 42-kDa subunit which covalently interacts with DNA (RgyA) and a 138-kDa subunit which binds ATP (RgyB). We have now cloned and sequenced the genes for both subunits of this enzyme.

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The widespread application of polymerase chain reaction and related techniques in biology and medicine has led to a heightened interest in thermophilic enzymes of DNA metabolism. Some of these enzymes are stable for hours at 100 degrees C, but no enzymatic activity on duplex DNA at temperatures above 100 degrees C has so far been demonstrated. Recently, we isolated topoisomerase V from the hyperthermophile Methanopyrus kandleri, which grows up to 110 degrees C.

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Reverse gyrase, an ATP-dependent topoisomerase that positively supercoils DNA, has been purified to near-homogeneity from the hyperthermophile Methanopyrus kandleri. It migrates on SDS-polyacrylamide gel electrophoresis as two principal bands with apparent molecular masses of 150 and 50 kDa. Both proteins remain associated throughout all chromatographic steps.

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DNA topoisomerase V is a novel prokaryotic enzyme related to eukaryotic topoisomerase I. The enzyme is a type I DNA topoisomerase and is recognized by polyclonal antibody against human topoisomerase I. We describe its purification from the hyperthermophilic methanogen Methanopyrus kandleri.

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The DNA topoisomerases are ubiquitous enzymes that fulfil vital roles in the replication, transcription and recombination of DNA by carrying out DNA-strand passage reactions. Here we characterize a prokaryotic counterpart to the eukaryotic topoisomerase I in the hyperthermophilic methanogen Methanopyrus kandleri. The new enzyme, called topoisomerase V, has the following properties in common with eukaryotic topoisomerase I, which distinguish it from all other known prokaryotic topoisomerases: (1) its activity is Mg(2+)-independent; (2) it relaxes both negatively and positively supercoiled DNA; (3) it makes a covalent complex with the 3' end of the broken DNA strand; and (4) it is recognized by antibody raised against human topoisomerase I.

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