Congruence analysis and combining of molecular genetic and morphological data in zoological systematics

A new algorithmic approach is proposed for congruence analysis of different types of data in zoological systematics. The algorithm is tested on actual data. A high degree of congruence is shown for morphometric and genetic distances in the tested set of species. Two directions of variation in both trait spaces have clearly appeared. The first direction discriminates families; the second discriminates orders. The traits responsible for these differences have been revealed. After uniting both distance matrixes, the morphological one and the molecular genetic one, into a single matrix, and displaying the summarized distances between species on a plane, the configuration of species remained principally unchanged. The principal directions of variations were preserved and marked the differences between orders, families, and genera.     

Rapid Chemical Synthesis of Oligodeoxyribonucleotides by the Improved Phosphotriester Method

Abstract

An efficient phosphotriester methodology based on the use of condensing agents in the presence of several new nucleophilic catalysts has been developed.     

The heterochromatin regions of the mitotic chromosomes in cattle]

Cytochemical and molecular peculiarities of heterochromatic regions of bovine chromosomes have been studied, using specific fluorochrome staining induced decondensation, in situ hybridization, pretreatment of restriction enzymes. The heterochromatin of autosomes demonstrated a strong homogeneity. In chromosome Y two small specific heterochromatic regions were found lacking a long repeated tandem block of nucleotides enriched in GC base pairs and having no tandem block of Bkm repeats (10(4) b.p.). This class repeats are probably interspersed in the bovine genome. A rather seldom character of mammalian karyotypes is the absence of cytochemical heterochromatin in the X chromosome.     

New efficient sulfurizing reagents for the preparation of oligodeoxyribonucleotide phosphorothioate analogues.

A set of new sulfurizing agents representing disulfides of arylsulfonic acids has been developed for the automated synthesis of phosphorothioate oligonucleotide analogues via the phosphoramidite method. These reagents, such as bis(benzenesulfonyl)disulfide, bis(p-toluenesulfonyl)disulfide, bis(p-methoxybenzensulfonyl)disulfide, and bis (p-chlorobenzenesulfonyl) disulfide, are easily prepared crystalline solid compounds. They are relatively inexpensive, easy to handle, and efficiently convert internucleotide cyanoethyl phosphite to the phosphorothioate triester within 1-2 min. The efficiency of phosphorothioate oligonucleotide synthesis with the use of these reagents is comparable to that of phosphodiester oligonucleotides.     

<Emphasis Type="Italic">Lactobacillus fermentum</Emphasis> 90 TC-4 taxonomic status confirmation using whole genome sequencing and MALDI TOF mass spectrum

With the use of whole genome sequencing, the taxonomic status of Lactobacillus fermentum 90 TC-4 strain from Russian collections were studied. Complex analysis of phenotypical and genetic properties was conducted using phenotypic and molecular genetic methods. The main characteristics of the genome and biochemical activity profile of the strain were determined. A comparative analysis of the mass spectrum of ribosomal proteins of the strain, its biochemical properties, a fragment of 16S rRNA gene sequencing, and the entire genome revealed that the present strain belongs to the species L. fermentum, confirming its taxonomic status in accordance with modern taxonomy.     

The role of environmental factors for the composition of microbial communities of saline lakes in the Novosibirsk region (Russia)

Background

Nothing is currently known about microbial composition of saline lakes of the Novosibirsk region and its dependence on physical-chemical parameters of waters. We studied the structure of microbial communities of saline lakes of the Novosibirsk region and the effect of physical-chemical parameters of waters on microbial communities of these lakes.

Results

According to the ion content, the lakes were classified either as chloride or chloride-sulfate types. Water salinity ranges from 4.3 to 290 g L⁻¹. Many diverse microbial communities were found. Filamentous and colonial Cyanobacteria of the genera Scytonema, Aphanocapsa, and/or filamentous Algae dominated in littoral communities. Spatial and temporal organization of planktonic microbial communities and the quantities of Archaea and Bacteria were investigated using fluorescent in situ hybridization. We have found that the dominant planktonic component is represented by Archaea, or, less frequently, by Bacteria. Various phylogenetic groups (Bacteria, Archaea, Algae, and Cyanobacteria) are nonuniformly distributed. The principal component analysis was used to detect environmental factors that affect microorganism abundance. We found the principal components responsible for 71.1 % of the observed variation. It was demonstrated that two-block partial least squares was a better method than principal component analysis for analysis of the data. We observed general relationships between microbial abundance and water salinity.

Conclusions

We have performed the first-ever study of the structure of the microbial communities of eleven saline lakes in the Novosibirsk region along with their physical-chemical parameters of waters. Our study demonstrates that saline lakes in the Novosibirsk region contain a unique microbial communities that may become a prolific source of microorganisms for fundamental and applied studies in various fields of ecology, microbiology, geochemistry, and biotechnology, and deserve further metagenomic investigation.