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A study of ITS1 of 28 specimens of eight species of Schistidium from well-separated populations in Russia and northwest Europe revealed that there are very big differences between species (up to 16 substitutions and 256 indels), whereas within the species differences in DNA there are very few (none to four substitutions and none to six indels). These results strongly support the narrow species concept in Schistidium. Schistidium papillosum is represented by two quite distinct genotypes and probably needs further splitting. [ABSTRACT FROM AUTHOR]

Molecular phylogenetic analysis of 66 representatives of haplolepidous mosses showed polyphylia of Ditrichaceae. According to the data obtained, the structure of the peristome, as well as features of the gametophyte on which a family traditionally allocated, arose independently in different groups of haplolepideous mosses. At least six genera (Distichium, Saelania, Eccremidium, Garckea, Rhamphidium, and Wilsoniella) should be excluded from the Ditrichaceae family, while Saelania and Distichium should be assigned even to another order. The loss of the peristome and forming of cleistocarpous capsules also occurs independently in at least two lineages of Ditrichaceae s. str., and in representatives of several lineages of Pottiaceae, a family derived from this group. Ditrichum, the type genus of Ditrichaceae, is also polyphyletic, species of this genus belong to two clades. It was concluded that parallel lines of the morphological variability in this group of mosses occur and its phylogeny need to be resolved based on molecular data.

The phylogeny of Schistidium (Bryophyta, Grimmiaceae) was studied on the basis of nucleotide sequences of internal transcribed spacers ITS1-2 of nuclear DNA and trnT-trnD region of chloroplast DNA. The consistency of phylogenetic trees constructed from nuclear and chloroplast sequences was shown. A basal grade and two large clades were resolved on the phylogenetic trees. Morphological characteristics specific for these clades were described. ITS1 and ITS2 secondary structures of Schistidium species were modeled using thermodynamic criteria. Four different structures of the longest ITS1 hairpin were identified. Possible paths of Schistidium evolution were considered based on the four types of ITS1 secondary structure and phylogenetic trees.

Strains (103) of yeast from Pichia genus: P. anomala, P. guilliermondii and P. membranaefaciens species have been investigated. The researchers have found 87 strains (84.5%) capable to form extracellular and surface lectins with activity to 512 hemagglutinating units. The overwhelming number of strains (75.7-92.6%) synthesized lectins of the both forms. Considerably less quantity of lectin producers of some form--extracellular or surface ones--have been found. Availability of producers of extracellular lectins was characteristic to greater extent of the yeast of P. anomala and P. guilliermondii, and producers of surface lectins--mainly of P. guilliermondii. The most active producers of lectins have been isolated from human and animal organisms, soils and wine.

Life cycles of Candida utilis (Henneberg) Lodder et Kreger-van Rij imperfect yeast (13 strains) used in industry were the study subject. When the strains were mated, we detected one of the stages of sexual process--conjugation of cells of the opposite mating type. Most of the studied cultures conjugated on the 2d-3d day. No ascospores were formed. Haploidy and heterothallism of the studied C. utilis strains were confirmed by hybridization of auxotrophic mutants. Based on PCR assay results, the yeasts are demonstrated to belong to the ascospore perfect yeast species of Pichia jadinii (A. et R. Sartory. We ill et Meyer, Wickerham) Kurtzman.

Hemagglutinating properties of culture liquid and cells of 142 yeast strains of species Saccharomyces cerevisiae, Kluyveromyces marxianus, K. dobzhanskii, K. lactis var. lactis and K. lactis var. drosophilarum, isolated from various sources have been studied. A capacity of yeast (44% of the studied strains) to synthesize both lectins bound to a cell and extracellular lectins has been established; the latter have been found in yeast for the first time.

Based on a study of 200 lactic-acid bacteria monocultures and 30 associating lactic bacteria and yeasts cultures, a stable association was created formed by Leuconostoc oenos, Pediococcus pentosaceus and Saccharomyces cerevisiae yeasts, intended for the biological deacidification of wine. Physiology of microorganisms and their effect on the wine chemical composition was studied. By means of selective association, high quality fine wines were produced from the high-acid wines.

Effects of balis-2 on exploratory activity in the open field and elevated plus-maze, attention to sensory stimuli of different modalities, elaboration and retention of conditioned reflexes with food reinforcement, were studied in rats under stress. Prolonged treatment of rats with balis-2 seems to normalise integrative activity and metabolism of serotonine and dopamine in the animal brain.

Quantitative and species compositions of yeast contaminating eggs, fry and fingerlings of Salmo gairdneri Rich under artificial breeding have been studied. Prevalence of species of genera Candida, Rhodotorula, Cryptococcus and Debaryomyces is noted. Yeast isolated from perished eggs and sick fry do not possess pathogenic properties. Certain strains of yeast make stimulating effect on the studied microorganisms.

Yeast flora composition has been studied in natural populations of blood-sucking mosquitoes of genera Aedes. Anopheles and Culex dwelling in the territory of Ukraine. The authors have distinguished 18 yeast species belonging to 7 genera. Species Candida famata, C. (Yarrowia) lipolytica as well as the yeast of genera Rhodotorula and Cryptococcus dominate on the larvae and imago of mosquitoes. The distinguished strains are the components of normal microflora of blood-sucking mosquitoes and take no pathogenic effect on the laboratory culture of mosquitoes Aedes aegypti.