Viktoria Stepanova

Learn More
Living cells maintain a steady state of biochemical reaction rates by exchanging energy and matter with the environment. These exchanges usually do not occur in in vitro systems, which consequently go to chemical equilibrium. This in turn has severely constrained the complexity of biological networks that can be implemented in vitro. We developed(More)
Beer is a natural product and is a multicomponent system that has both positive and negative consumer properties. Organoleptical off-flavors of beer are difficult to eliminate. Yeasts are the main active component of the system. The relationship between beer quality and yeast usage is well known. New industrial strains for brewery are continuously(More)
Yeast mutants resistant to a toxic lysine analog, thialysine were obtained by a method described in the literature. A strain excreting the maximum amount of lysine (0.45 g/l) was selected from these mutants. The intracellular content of lysine was also increased by 30%. The genetic nature of lysine overproduction was studied in this strain. An increase in(More)
We have crossed irradiated and unirradiated genetically marked haploid yeast cells and studied the influence of gamma-irradiation on the yield of nuclear-cytoplasmic haploid hybrids (cytoductants). In the first cross, the cytoductants possessed the irradiated cytoplasm (mitochondrions) and unirradiated nuclei, in the second cross they possessed the(More)
Integration of the episomic chimeric plasmid pYF91 into yeast chromosomes has been studied. Plasmid insertion into the chromosomes was observed to occur with the frequency of 4 X 10(-8). 379 integrants were selected from the highly unstable (cir0) transformants. The fact of plasmid integration into particular chromosomes was confirmed for 318 integrants.(More)
The methods for chimeric chromosomes' destabilization and the standard tetrad analysis have been used for mapping of the yeast genes XRS2 and HIM1. The genes are localized in the right arm of chromosome IV in the following order: XRS2-31cM-ADE8-28.5cM-HIM1.
The data on mapping the episomal plasmid integration sites in yeast chromosomes I, III, IV, V, VII, XV are presented. In addition to the integration site at leu2 of chromosome III localized earlier, 6 more loci containing apparently the homologous yeast transposons, with a copy in a plasmid, were defined. The fact of plasmid integration was proved by colony(More)
The described system of safety assurance of cryopreserved allogeneic and xenogeneic dermoepidermal transplants comprises serological examination of deceased tissue donors, long-term storage of sera of all donors, microbiological control of prepared allogeneic and xenogeneic dermoepidermal grafts, labelling of released tissue grafts and monitoring of(More)
When crossing the genetically marked yeast strains obtained from the Gif collection we observed the appearance of haploid nucleo-cytoplasmic hybrids carrying the 3 nuclear markers of the rho- parent and the mitochondrial markers (rho+ ER CR) of the other parent. The frequency of such cytoduction was about 1 per cent. The mitochondrial markers ER and CR were(More)