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T V Koronelli

Publications and source records attributed to T V Koronelli.

At least 19 recordsLinked to original sources
PubMed1993

[Inclusion of labeled precursors of macromolecular compounds in the mycobacterial cells in the presence of DP-2 preparation].

The changes in the inclusion of 3H-phenylalanine, methyl-3H-thymidine, [2-14C]-thymidine and [5-3H]-uridine in the cells of pathogenic M. bovis-8, opportunistic M. fortuitum and saprophitic M. phlei, M. B-5 were comparatively investigated in introduction of 0.01 and 0.10% concentrations of the drug DP-2. It is shown that 0.10% DP-2 completely stops the radionuclides supply to the cells. It is suggested that the target of the drug may exist in the sphere of amino acid biosynthesis. The presence of DP-2 is capable of disturbing transport of substances to the cells.

Amino Acids↗
PubMed1988

Investigation of the lipids of saprophytic mycobacteria in the U.S.S.R.

Three trends in the investigations of the specific lipids of rhodococci and related microorganisms are reflected: isolation and structural determination of new complex lipids, elucidation of the role of specific lipids in the cells and application of lipid composition for diagnostic studies of rhodococci and related organisms. Two groups of peptidolipids, differing in chromatographic mobility and peptide chain structure, have been found in the cells of Rhodococcus erythropolis. The compounds within each group differ in acyl moieties. Three peptidolipids of the polar group include glucose, so they are peptidoglycolipids. Glycolipids are represented by trehalose derivates. Trehalose dimycolate (cord factor) is dominant. Data concerning the role of lipids in typical features of rhodococci as the lipophilic cell wall, the ability to up-take a hydrophobic substrate and the resistance to influences from outside are given. Examples of application of mycolic acid composition in taxonomy of rhodococci and morphologically similar bacteria are given.

Lipids↗
PubMedDate not supplied

[Extracellular metabolites of hydrocarbon-oxidizing bacteria as a substrate for sulfate reduction].

The relationship between bacterial oxidation of hydrocarbons and sulfate reduction was studied in the experimental system with liquid paraffin was used as a source of organic compounds inoculated with silt taken from a reservoir. Pseudomonads dominated in the hydrocarbon-oxidizing silt bacteriocenosis. However, Rhodococcus and Arthrobacteria amounted to not more than 3%. Arthrobacteria dominated the microbial association formed in the paraffin film of the model system. Sulfate-reducing bacteria were represented by genera Desulfomonas, Desulfotomaculum, and Desulfovibrio. The growth of sulfate-reducing bacteria in media containing with paraffin, successive products of its oxidation (cetyl alcohol, stearate, and acetate), and extracellular metabolites of hydrocarbon-reducing bacteria was studied. The data showed that sulfate-reducing bacteria did not use paraffin or cetyl alcohol as growth substrates. However, active growth of sulfate-reducing bacteria was observed in the presence of stearate and extracellular water-soluble or lipid metabolites of Arthrobacteria.

Gram-Negative Anaerobic Bacteria↗
PubMedDate not supplied

[Intrinsic waxes of saprophytic mycobacteria].

The ability of soil mycobacteria for the synthesis of true waxes may be revealed on media with hydrocarbons. Most strains produced only traces of wax, and some strains (2 out of 62) in considerable amounts (over 1% of dry biomass). The chemical composition of the wax depends on the structrue of oxidized substrate: a mixture of two to three homologues with the molecular weights of 452, 480 and 508, respectively, is formed on a medium with hexadecane, and a mixture of seven homologues with the homologous difference of 14 in the case of glucose.

Alkanes↗
PubMedDate not supplied

[Role of lipids in the acid resistance of saprophytic mycobacteria].

The resistance of saprophyte mycobacteria to acids increases on a medium containing paraffin. The content of free lipids and mycolic acids in the cells of Mycobacterium convolutum assimilating the hydrocarbon increases cf. that in the cells grown on meat-peptone broth. The structure of mycolic acids was established after studying their methyl esters by mass spectrometry. The cells grown on the medium with hexadecane contain mycolic acids C32--C36, with C34- and C36-compounds prevailing and the aliphatic chain in alpha-position containing 10, 11, 12, and 14 C-atoms. The cells cultivated on meat-peptone broth contain another type of acids of high molecular weight (greater than 700).

Alkanes↗
PubMedDate not supplied

[Distribution of hydrocarbon and wax in the cells of Mycobacterium ceroformans].

The distribution of hydrocarbon and wax was studied in the cells of Mycobacterium ceroformans. The cells were disintegrated in French press and the content of hydrocarbon and wax was determined in the cell-free extracts. Hydrocarbon and wax are accumulated in the cell walls of Mycobacterium ceroformans.

Cell Membrane↗
PubMedDate not supplied

[Bacterial succession on n-alkanes under the conditions of sulfate reduction].

The dynamics of species composition of a hydrocarbon-oxidizing bacteriocenosis of a ground suspension of Mozhaisk Reservoir has been studied. The bacteriocenosis was undergoing development in a paraffin film (model association composed of sulfate-reducing bacteria and hydrocarbon-oxidizing bacteria). The type of bacterial succession did not depend on the depth, from which ground samples were collected. Two microbial species (Pseudomonas sp. and Arthrobacter globiformis) were absolutely dominant. Pseudomonas sp. was dominant at the early and intermediate stages of the succession, whereas A. globiformis was present in the hydrocarbon-oxidizing bacteriocenosis throughout the whole period of the succession. There was a trend toward a gradual increase in the ratio of A. globiformis, and, by the end of the experiment, Pseudomonas sp. was replaced by A. globiformis almost completely. The bacterial species Micrococcus sp. and Rhodococcus erythropolis were minor components of the hydrocarbon-oxidizing bacteriocenosis under the conditions of sulfate reduction. The succession of species of hydrocarbon-oxidizing bacteria in the paraffin film of the model association reflects both the life strategy of the bacterial species under study and the degree of their tolerance to products of sulfate reduction.

Alkanes↗
PubMedDate not supplied

[The role of low-molecular-weight nitrogen compounds in the osmotolerance of Rhodococcus erythropolis and Arthrobacter globiformis].

Investigations showed that Rhodococcus erythropolis E-15 and Arthrobacter globiformis 2F cells respond to osmotic shock by increasing the synthesis of free amino acids, primarily glutamic acid (80% of the intracellular free amino acid pool). The osmoprotective role of glutamic acid follows from its beneficial effect on the growth of bacteria in high-salinity media. It was found that the addition of this amino acid to the growth medium at a concentration of 2 mM shortened the lag phase and increased the growth rate and biomass yield of either of the two bacteria. The addition of another osmoprotectant, trehalose, to the high-salinity growth medium of R. erythropolis E-15 at the same concentration (2 mM), restored the growth parameters of this bacterium to the control values.

Amino Acids↗
PubMedDate not supplied

[Esterase activity of hydrocarbon-oxidizing bacteria].

The activity of esterase was studied in bacteria oxidizing hydrocarbons and belonging to the genera Rhodococcus, Arthrobacter and Pseudomonas. Indophenyl acetate was used as a substrate of the reaction catalysed by the enzyme. Exocellular esterases were not found. Endocellular esterases differed in their activity and thermostability both among the genera and among species of one and the same genus.

Arthrobacter↗
PubMedDate not supplied

[Hydrocarbon-oxidizing microflora from the water of the Baltic sea and Kurshsky bay polluted after a fuel oil spill].

Microbiological studies were conducted in the water of the Baltic sea and the Kurshsky bay polluted with mazut as the result of a tanker wreck in November 1981 as well as in the water of nonpolluted regions. Within the summer of 1982 and 1983, 755 bacterial strains were isolated from water samples taken at three different depths. Bacteria belonging to the genera Pseudomonas, Rhodococcus + Mycobacterium and Arthrobacter predominated in the hydrocarbon-oxidizing cenoses of the Baltic sea and the Kurshsky bay. The central part of the Baltic sea pure from mazut did not differ from the polluted regions in the qualitative composition of the hydrocarbon-oxidizing bacterial flora. Rhodococci and mycobacteria prevailed in the water near harbours, and pseudomonades, in the open waters. The greatest variety of species was found at a depth of 1 m. The proportion between the predominating genera of hydrocarbon-oxidizing bacteria was not stable. The state of studies conducted with the hydrocarbon-oxidizing microflora is analysed and the factors causing discrepancies are discussed. One must keep in mind that it is necessary to use a strictly elective medium and to examine cultures with a microscope many times throughout their growth in the isolation and identification of hydrocarbon-oxidizing bacteria. The interrelationship is analysed between the predominant genera of hydrocarbon-oxidizing bacteria.

Atlantic Ocean↗