Vol 7, No 4 (2017)

The review considers problems of evolution of cyanobacteria, including geobiological aspects of the origin of these prokaryotes, the appearance of oxygenic photosynthesis, multicellularity, and diazotrophy, from the standpoint of comparative phylogenomics. Special attention is paid to the contribution of different genetic processes (mutations, genome rearrangements, genome reduction, horizontal gene transfer) to the evolution of cyanobacterial genomes. The patterns of genetic variability associated with (a) the level of gene polymorphism, (b) the expansion of gene families, and (c) genomic rearrangements mediated by mobile elements are summarized. Based on the data of genomic phylogeny, a modified scheme of a possible sequence of evolutionary stages in the main taxonomic groups of cyanobacteria was constructed on the scale of the geological history of the Earth.

For decades, acclimation was understood as a laboratory method for the obtainment of material applicable for comparison by physiological indicators. Based on the published data and studies on salinity adaptations performed at the White Sea Biological Station of the Zoological Institute, acclimation can be recognized as a biological phenomenon of phenotypic adaptation characterized by the following features: oscillation mode of function changes; duration of 1–4 weeks; reversibility; and regulating mechanisms via gene activity. Some examples of medical situations related to acclimation are given. Approaches for the assessment of potential tolerance, which is suggested as a synonym for reaction norm, are recognized to be especially important ecological aspects of acclimation.

This article considers the molecular genetic and ecological approaches to solving the problem of the origin of the plague-causative agent microbe Yersinia pestis. The initial conditions of the conversion of the clone of saprozoobiont pseudotuberculosis microbe Yersinia pseudotuberculosis O:1b to the population of plague microbe Yersinia pestis are described. It is shown that a remote biogeocenotic precondition for speciation was the aridization of Central Asian landscapes, which resulted in the formation of the species-specific behavior of the Mongolian tarbagan marmot (Marmota sibirica): the arrangement of plugs in wintering burrows with the use of their own excrement. The last maximal Sartan cooling, which covered the areas of Central Asia 22000–15000 years ago, became a recent biogeocenotic precondition that served as a direct inducer of the speciation process. The deep freezing of the ground caused a shift in the behavior of one of the components of biocenosis, namely, the larvae of the marmot flea Oropsylla silantiewi: they began to change from saprophagy to hematophagy in winter months. This phenomenon led to the direct (traumatic) contact of excrement with blood in the oral cavity of marmots during hibernation. The traumatic penetration of pseudotuberculosis microbe into the blood of Mongolian marmots for the whole population during hibernation created conditions for the implementation of stable bacteremia and the development of the original epizootic M.sibirica–O.silantiewi–Y. pestis plague system. The psychrophilic properties and virulence are considered necessary preadaptive properties for pseudotuberculosis microbe to invade the host–parasite (rodent–flea) environment.

The introduction of genetic engineering methods into the production of live influenza vaccines provides significant optimization of separate stages of this process. In recent years, special attention has been paid to a method based on the direct incorporation of well-known and well-studied mutations into the genome of epidemic variants of influenza virus. Such virus obtains the ts- and att phenotypes and can be used for the production of live influenza vaccines. The article discusses the applications of this approach and problems associated with its use in medical and veterinary vaccinology.

The review summarizes the current knowledge about the molecular genetic markers associated with athletic performance in various sports. Some variations in DNA sequences are associated with specific phenotypes involved in the athletic performance, including endurance capacity, muscle performance, body mass composition, body morphological characteristics, and susceptibility to injuries.