Erratum to: "Gas chromatography-mass spectrometry in the taxonomy of Miscanthus".

Vavilovskii Zhurnal Genetiki i Selektsii = Vavilov Journal of Genetics and Breeding. 2019;23(8):1076-1081 (in Russian) Page 1081, in Acknowledgements instead of This work was supported by State Budgeted Project АААА-А17-117092070032-4. should read This work was supported by State Budgeted Project 0259-2019-0011. The original article can be found under DOI 10.18699/VJ19.583.

An integrated method for taxonomic identification of microorganisms.

For accurate species-level identification of microorganisms, researchers today increasingly use a combination of standard microbiological cultivation and visual observation methods with molecular biological and genetic techniques that help distinguish between species and strains of microorganisms at the level of DNA or RNA molecules. The aim of this work was to identify microorganisms from the ICG SB RAS Collection using an integrated approach that involves a combination of various phenotypic and genotypic characteristics. Key molecular-genetic and phenotypic characteristics were determined for 93 microbial strains from the ICG SB RAS Collection. The strains were characterized by means of morphological, physiological, moleculargenetic, and mass-spectrometric parameters. Specific features of the growth of the strains on different media were determined, and cell morphology was evaluated. The strains were tested for the ability to utilize various substrates. The strains studied were found to significantly differ in their biochemical characteristics. Physiological characteristics of the strains from the collection were identified too, e.g., the relationship with oxygen, type of nutrition, suitable temperature and pH ranges, and NaCl tolerance. In this work, the microorganisms analyzed were combined into separate groups based on the similarities of their phenotypic characteristics. This categorization, after further refinement and expansion of the spectrum of taxa and their metabolic maps, may serve as the basis for the creation of an "artificial" classification that can be used as a key for simplified and quicker identification and recognition of microorganisms within both the ICG SB RAS Collection and other collections.

Dynamics of DNA-protein complex formation in rat liver during induction by phenobarbital and triphenyldioxane.

CYP2B gene expression in liver of rats treated with phenobarbital and triphenyldioxane at early stage of induction (40 min-18 h) was studied using electrophoretic mobility shift assay (EMSA) and RT-PCR. During first 6 h after induction, differences in the dynamics of formation of DNA-protein complexes were shown for each inducer. Later (18 h after induction), the intensity pattern of these complexes became the same for both phenobarbital and triphenyldioxane treated animals. This suggests the existence of specific signaling for each inducer only in early stages of CYP2B activation. Increase in nuclear protein (possible transcription factor) binding to Barbie-box regulatory sequence of CYP2B genes was accompanied by their increased expression. Thus, we have demonstrated for the first time that early stages of induction (40 min and 3 h after administration of phenobarbital and triphenyldioxane, respectively) are accompanied by activation of nuclear proteins that can bind to Barbie-box element of CYP2B. Although various chemical inducers cause distinct activation of such binding, this process involves activation of gene transcription.

Bifunctional compound study of the active-centre location of cytochrome P-450 in a microsomal membrane ('float' molecules method).

A new approach, which we call 'float' molecules method for the determination of the active-centre location of cytochrome P-450 in a microsomal membrane, is proposed. We have synthesized new bifunctional compounds with the general formula: R-(CH2)n-S-CH2-CH(PO3H2)2, where n = 0,3,5,6,7,10 and R is a naphthalene-containing radical. The compounds inhibit oxidation and binding of cytochrome P-450 substrates of type I (naphthalene, aminopyrine) and of type II (aniline). The inhibition is of a competitive character. Compounds (I-V) neither affect NADPH-cytochrome c reductase, nor induce conversion of cytochrome P-450. A lipid-soluble fluorescent probe (1,6-diphenyl-1,3,5-hexatriene) has been used to show that these compounds do not affect melting of microsomal membrane. The 31P-NMR method has demonstrated compound (III) to be incorporated into microsomal membrane so that the hydrophilic part is in the water phase. The data obtained make it possible to estimate the distance (r) between the membranes surface and Fe3+ in the active centre of the enzyme (r less than or equal to 20 A) under the assumption that all molecules of cytochrome P-450 are equally remote from the membrane surface.