Pulse-electrotypes of Listeria monocytogenes strains, isolated in Moscow

The characterization of the pulse-electrotypes of L. monocytogenes, isolated in 2003-2004 in Moscow from different sources, is presented. Among the cultures, isolated from humans, one outbreak pulse electrotype was detected and from different objects in buildings where a wide variety of food products was produced several probably related and unrelated pulse-electrotypes were obtained. The conclusion was made that several independent L. monocytogenes clones existed on the territory of Moscow, and many products supplied to retail trade and public catering enterprises were contaminated with these clones. Pulse electrophoresis was shown to be the most effective method for intraspecific typing and the study of the molecular epidemiology of listeriosis. Grounds for the necessity to improve the microbiological diagnostics of L. monocytogenes infection are given.     

Characterization of Escherichia coli strains O157:H7, isolated on the territories of the Central Federal District

The characterization of E.coli strains O157:H7, isolated from humans and animals on some territories of the Central Federal District, is presented. Among the isolates from human outbreaks, related and, probably, related cultures prevailed, while among the isolates obtained from different animals mainly unrelated cultures have been detected. A conclusion has been made concerning the existence of several independent zoonotic reservoirs of E. coli O157:H7 infection on this territory. The advantages and drawbacks of the use of pulse electrophoresis in the characterization of E. coli O157:H7 are discussed. Grounds are given for the necessity of the patients examination with hemorrhagic enetrocolitis for the presence of E. coli O157:H7, as well as for the expediency of having a special item for the registration of this E. coli infection in relevant statistical forms.     

Adaptation of subpopulations of the Norway spruce needle endophyte Lophodermium piceae to the temperature regime

Lophodermium piceae represents the most common Norway spruce needle endophyte. The aim of this study was to find out whether subpopulations of L. piceae in climatically different environments (in which Norway spruce occurs natively) are adapted to local thermal conditions. L. piceae’s ability for thermal adaptation was investigated by determining growth rates of 163 isolates in vitro at four different temperatures: 2, 6, 20 and 25 °C. Isolates were obtained between 1995 and 2010 from apparently healthy needles sampled in Finland, Poland, Switzerland, Italy and southeastern Siberia. The sampling sites represent seven climatically distinct locations. Results were evaluated in relation to the age and geographic origin of the isolate, in addition to the highest and lowest average monthly temperature of the sampling location. We found a significant correlation between the growth rate and the age of the isolate at 25 °C. Variation in growth rates between subpopulations was low compared to within subpopulations. Only at 2 °C did statistically significant differences between the average growth rates of subpopulations emerge. These results suggest that L. piceae covers the whole distribution area of Norway spruce but that generally the thermal reaction norm of its subpopulations has not changed according to local temperature ranges, despite high contrast in thermal conditions across this vast area. Therefore, it would appear that the thermal environment is not a crucial factor in assessing the fitness of this fungal species within the native range of Norway spruce.     

Soil and geobotanical profiling in phytocenotic studies at junctions of taiga and extrazonal steppes on the western shore of Lake Baikal

The formation of phytocenoses at the junction of taiga and extrazonal steppes has been studied in the center of the western Baikal lakeshore. Geobotanical profiling, including soil profiling, has been carried out in one of the key areas. The structure and dynamics of community formation in the conditions of interrelated development of light coniferous taiga and extrazonal steppes have been revealed. Edaphic conditions and location of phytocenoses are the main initiating environmental factors which determine the trend of floral cover development in this part of the western Baikal lakeshore.     

Larvae of related Diptera species from thermally contrasting habitats exhibit continuous up-regulation of heat shock proteins and high thermotolerance

A population of Stratiomys japonica, a species belonging to the family Stratiomyidae (Diptera), common name ‘soldier flies’, occurs in a hot volcanic spring, which is apparently among the most inhospitable environments for animals because of chemical and thermal conditions. Larvae of this species, which naturally often experience temperatures more than 40 °C, have constitutively high concentrations of the normally inducible heat-shock protein Hsp70, but very low level of corresponding mRNA. Larvae of three other species of the same family, Stratiomys singularior, Nemotelus bipunctatus and Oxycera pardalina, are confined to different type semi-aquatic habitats with contrasting thermal regime. However, all of them shared the same pattern of Hsp70 expression. Interestingly, heat-shock treatment of S. japonica larvae activates heat-shock factor and significantly induces Hsp70 synthesis, whereas larvae of O. pardalina, a species from constant cold environment, produce significantly less Hsp70 in response to heat shock. Adults of the four species also exhibit lower, but detectable levels of Hsp70 without heat shock. Larvae of all species studied have very high tolerance to temperature stress in comparison with other Diptera species investigated, probably representing an inherent adaptive feature of all Stratiomyidae enabling successful colonization of highly variable and extreme habitats.     

Soil-geobotanical profiling in studying the communities forming under conditions of extrazonality of the Barguzinskaya Basin steppes (Northeastern Pribaikalye)

This paper provides results from studying the formation features of plant communities in extrazonal steppes of the Barguzinskaya Basin, Northeastern Pribaikal’e. The soil-geobotanical profiling was carried out on one of the key sections of the study area. The structure of the communities of contacting light-coniferous taiga and extrazonal steppes is revealed. The edaphic conditions and location of the plant communities reflect the trend in the vegetation-cover development of this part of the Baikal region.     

Molecular phylogeny of fungus gnats (Diptera: Mycetophilidae) revisited: position of Manotinae,Metanepsiini, and other enigmatic taxa as inferred from multigene analysis

The phylogeny of selected genera from four subfamilies of fungus gnats (Diptera: Mycetophilidae) – Manotinae, Leiinae, Sciophilinae and Gnoristinae (including Metanepsiini) – is reconstructed based on the combined analysis of five mitochondrial (12S, 16S, COI, COII, cytB) and two nuclear (28S, ITS2) gene markers. Results of the different analyses all support Manotinae as a monophyletic group, with Leiinae as the sister group. Allactoneura DeMeijere is nested in the monophyletic and strongly supported clade of Leiinae. The tribe Metanepsiini is revealed as paraphyletic and the genera Metanepsia Edwards and Chalastonepsia Søli do not appear to be closely related. The genera Docosia Winnertz, Ectrepesthoneura Enderlein, Novakia Strobl and Syntemna Winnertz were placed with a group of genera included traditionally in the Gnoristinae. The monophyly of Dziedzickia Johannsen and Phthinia Winnertz is not supported. The genera of Sciophilinae (excluding Paratinia Mik but including Eudicrana Loew) form a monophyletic group in the Bayesian model.