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T P Turova

Publications and source records attributed to T P Turova.

At least 19 recordsLinked to original sources
PubMed1988

[Identification of Listeria using molecular DNA-DNA hybridization].

The DNA-DNA hybridization method was used to study 4 species of bacteria of the genus Listeria. Concerning the DNA homology, L. monocytogenes strains may be divided into several species (in particular, the pathogenic forms may be isolated into independent taxon), in correlation with their biochemical and serological properties. Most of the studied strains of this species exhibit a high level of DNA homology--65-100%. Bacteria of the L. grayi and L. murrayi species are closely related to each other (90% of DNA homology), the reasonable suggestion being to unite them into a single species. L. denitrificans has 7% of DNA homology with the DNA of the other three species suggesting that it should be excluded from the genus Listeria.

Base Sequence↗
PubMed1985

The use of molecular hybridization to evaluate the divergence of some altered Rickettsia prowazekii strains.

Molecular DNA/DNA hybridization was used to investigate the degree of divergence of different Rickettsia prowazekii strains, namely strain Breinl, the vaccine strain E, its spontaneous erythromycin-resistant mutant, nitrosoguanidine-induced rifampicin-resistant mutant and a variant of strain E with increased virulence upon mouse lung passaging. Hybridization of highly polymerised rickettsial DNAs was carried out on nitrocellulose filters with in vitro labelled fragments of reference DNA of the Breinl strain. Nucleotide composition of the strains was also studied. The results obtained suggest the high degree of homology of nucleotide sequences in DNAs of R. prowazekii strains under study; the existing differences found are within the intraspecies range.

Animals↗
PubMed1983

Allomonads - a new group of microorganisms of the Vibrionaceae family.

A total of 24 strains of microorganisms with basic marks relating them to the family of Vibrionaceae were isolated from human faeces, liquid sewage and waters of surface reservoirs contaminated with sewage. The study of biological, cultural and biochemical characteristics, determination of phenotypic similarity according to Adanson-Sneath, investigation of DNA composition and extent of DNA hybridization by the methods of gene taxonomy induced us to establish taxonomic independence of the discovered strains at the level of the genus Allomonas gen. nov. with so far the only species A. enterica sp. nov.

Animals↗
PubMed1983

[Allomonads--a new group of microorganisms of the family Vibrionaceae. V. Taxonomic position of the allomonads based on a study of their DNA].

The DNA of Allomonas, a new group of microorganisms, has been studied to determine the taxonomic status of this group. In the nucleotide composition of the DNA of a typical representative of this group 57.4 mol % G + C have been revealed, which permits to sharply differentiate Allomonas from vibrios and Plesiomonas. A relatively low level of similarity between the DNA of Allomonas and that of other representatives of the family Vibrionaceae has been determined by the method of molecular DNA hybridization (6-18% of homologies), this level being approximately the same in vibrios, Plesiomonas and Aeromonas. These data indicate the necessity of regarding Allomonas as a separate genus of the family Vibrionaceae.

Base Sequence↗
PubMed1980

[Genome characteristics of a new group of microorganisms in the Vibrionaceae family].

A new group of microorganisms isolated from river and sewage water was studied by the method of molecular DNA-DNA hybridization and included into the family Vibrionaceae on account of their phenotypical properties. The genomes of the microorganisms belonging to this group proved to be highly similar (41-92% of homologies), which suggested that they were related on the genus level. The degree of similarity between the nucleotide sequences in the DNA of the bacteria under study and the DNA of other representatives of the family Vibrionaceae (the genera Vibrio, Beneckea, Aeromonas, Plesiomonas) amounting to 10-20% of homology indicates that the group of microorganisms under study forms a separate genus within the family Vibrionaceae.

Base Sequence↗
PubMed1979

[Similarity of the DNA mucleotide sequences of vibrios].

The systematic position of some Vibrio species was ascertained by the method of molecular DNA -- DNA hybridization. The DNA of the brine vibrios V. costicola and V. fischeri were shown to have about 10% of sequences homologous with DNA of a typical cholera vibrio (V. cholerae eltor No. 334). Similarity between the genomes of other representatives of the Vibrionaceae family, as well as in DNA hybridization of V. costicola and V. fischeri, was found to be approximately on the same level. All species included into the genus, Vibrio on account of their phenotypic characteristics may be considered to have essential differences in the structures of their genomes.

Base Sequence↗
PubMed1975

[More precise identification of the systematic position of marine bacteria by the method of DNA-DNA hybridization].

In the present work by the method of molecular DNA hybridization there was shown a low degree of affinity of the standard museum strains of cholera vibrios to the respresentatives of the sea species V. parahaemolyticus and V. alginolyticus, and also halophilic vibrios identified earlier on the basis of phenotypical characteristics of the nucleotide DNA composition as Marinovibrio. The presence of only 20--30% of homology in the DNA successiveness in cholera vibrios and the mentioned sea bacteria pointed to the necessity of exclusion of the latter from the Vibrio genus.

DNA, Bacterial↗
PubMedDate not supplied

[Roseinatronobacter thiooxidans Gen. Nov., sp. Nov., a new alkaliphilic aerobic bacteriochlorophyll-alpha-containing bacteria from a soda lake].

Several samples of microbial mat obtained from soda lakes of the Kunkurskaya steppe (Chita oblast) abundantly populated by purple bacteria were screened for the presence of heterotrophic alkaliphiles capable of oxidizing sulfur compounds to sulfate. This capacity was found in only one pigmented strain, ALG 1, isolated on medium with acetate and thiosulfate at pH 10. The strain was found to be a strictly aerobic and obligately heterotrophic alkaliphile. Growth on medium with acetate was possible within a narrow pH range from 8.5 to 10.4. The strain formed a reddish orange carotenoid and bacteriochlorophyll a. Pigments were synthesized only at high concentrations of nitrogen-containing organic compounds (peptone or yeast extract). The production of bacteriochlorophyll a was maximal under microaerobic conditions in darkness. Strain ALG 1 could oxidize sulfide, thiosulfate, sulfite, and elemental sulfur to sulfate. In heterotrophically growing culture (pH 10), thiosulfate was not oxidized until the late logarithmic phase. The sulfur-oxidizing activity was maximal at the most alkaline pH values. The notable increase in the efficiency of organic carbon utilization observed in the presence of thiosulfate suggested that the bacterium was a sulfur-oxidizing lithoheterotroph. The phylogenetic analysis of the 16S rRNA gene showed strain ALG 1 to be a member of the alpha-3 subgroup of proteobacteria and to constitute a distinct branch located between nonsulfur purple bacteria Rhodobacter and Rhodovulum. Based on the unique phenotypic properties and the results of phylogenetic analysis, the alkaliphilic isolate ALG 1 was assigned to a new genus and species Roseinatronobacter thiooxidans with the type strain DSZM-13087.

Alkalies↗
PubMedDate not supplied

[Physico-chemical and microbiological characteristics of groundwater from observation boreholes of a deep radioactive liquid waste repository].

A radioactive liquid waste repository was found to be a habitat of the rich microbial community with a high catabolic potential. Groundwater from a depth of 162-189 m contained aerobic saprotrophic and anaerobic fermentative, sulfate-reducing, and denitrifying bacteria. Nitrate-reducing bacteria residing in this groundwater were isolated in pure cultures. Based on the results of their physiological studies, 16S rRNA sequencing, and phylogenetic analysis, the microorganisms isolated were ascribed to one phylogenetic branch, the gamma-subclass of gram-negative bacteria. Among six isolates, four belonged to the genus Acinetobacter, whereas two others belonged to the genera Comamonas and Aeromonas. The data obtained indicate that the microflora of the repository can exert a certain effect on the chemical composition of the formation fluids and bearing rocks, as well as on the migration of radionuclides.

Bacteria↗
PubMedDate not supplied

[Physiological and phylogenetic diversity of thermophilic spore-forming hydrocarbon-oxidizing bacteria from oil fields].

The distribution and population density of aerobic hydrocarbon-oxidizing bacteria in the high-temperature oil fields of Western Siberia, Kazakhstan, and China were studied. Seven strains of aerobic thermophilic spore-forming bacteria were isolated from the oil fields and studied by microbiological and molecular biological methods. Based on the 16S rRNA gene sequences, phenotypic characteristics, and the results of DNA-DNA hybridization, the taxonomic affiliation of the isolates was tentatively established. The strains were assigned to the first and fifth subgroups of the genus Bacillus on the phylogenetic branch of the gram-positive bacteria. Strains B and 421 were classified as B. licheniformis. Strains X and U, located between B. stearothermophilus and B. thermocatenulatus on the phylogenetic tree, and strains K, Sam, and 34, related but not identical to B. thermodenitrificans and B. thermoleovorans, undoubtedly represent two new species. Phylogenetically and metabolically related representatives of thermophilic bacilli were found to occur in geographically distant oil fields.

Bacillus↗
PubMedDate not supplied

[Heliobacterium sulfidophilum sp. Nov. and Heliobacterium undosum sp. Nov.: sulfide-oxidizing Heliobacteria from thermal sulfidic springs].

Two new species of heliobacteria isolated from cyanobacterial mats of two alkaline sulfidic hot springs are formally described. Strains BR4 and BG29 are assigned to anoxygenic phototrophic bacteria of the family Heliobacteriaceae, since they possess the unique properties of this taxon: strict anaerobiosis, formation of bacteriochlorophyll g, the lack of extensive intracytoplasmic membranes and chlorosomes, an unusual cell wall structure, and phylogenetic relatedness to the low G + C gram-positive eubacteria. Based on the 16S rDNA sequence similarity, strains BR4 and BG29 are assigned to the genus Heliobacterium and described as two new species of this genus: Heliobacterium sulfidophilum sp. nov. and Heliobacterium undosum sp. nov. The G + C content of the DNA is 51.3 mol % in Hbt. sulfidophilum and 57.2-57.7 mol % in Hbt. undosum. The cells of Hbt. sulfidophilum are rods, and the cells of Hbt. undosum are slightly twisted spirilla or short rods. Both new bacteria are motile by peritrichous flagella. Hbt. sulfidophilum produces endospores. The new bacteria are strict anaerobes growing photoheterotrophically on a limited range of organic compounds. In the dark, they can switch from photosynthesis to the slow fermentation of pyruvate. Biotin is required as a growth factor. Both species are highly tolerant to sulfide (up to 2 mM at pH 7.5) and oxidize it photoheterotrophically to elemental sulfur; photoautotrophic growth was not observed. The temperature optimal for growth of Hbt. sulfidophilum and Hbt. undosum is 30-35 degrees C, and the optimal pH is 7-8.

Bacteria↗
PubMedDate not supplied

[Use of data from DNA-DNA hybridization and analysis of 16S rRNA genes for resolving taxonometric problems using the order Haloanaerobiales as an example].

In this review, the validity of evolutionary conclusions inferred from the quantitative estimates of the similarity between bacterial genes is evaluated using the order Halonanaerobiales as an example. The haloanaerobic phenotype is briefly characterized, as are some specific features that allow the order Haloanaerobiales to serve as a reference taxon. Phylogenetic analysis provides a set of standard quantitative criteria for ranking bacterial taxa, from species to families. Recommendations for the use of these standard criteria are given.

Clostridium↗