How to change the oligomeric state of a circular protein assembly: switch from 11-subunit to 12-subunit TRAP suggests a general mechanism

Many critical cellular functions are performed by multisubunit circular protein oligomers whose internal geometry has evolved to meet functional requirements. The subunit number is arguably the most critical parameter of a circular protein assembly, affecting the internal and external diameters of the assembly and often impacting on the protein's function. Although accurate structural information has been obtained for several circular proteins, a lack of accurate information on alternative oligomeric states has prevented engineering such transitions. In this study we used the bacterial transcription regulator TRAP as a model system to investigate the features that define the oligomeric state of a circular protein and to question how the subunit number could be manipulated.We find that while Bacillus subtilis and Bacillus stearothermophilus TRAP form 11-subunit oligomers, the Bacillus halodurans TRAP exclusively forms 12-subunit assemblies. Significantly, the two states of TRAP are related by a simple rigid body rotation of individual subunits around inter-subunit axes. We tested if such a rotation could be induced by insertion or deletion mutations at the subunit interface. Using wild type 11-subunit TRAP, we demonstrate that removal of five C-terminal residues at the outer side of the inter-subunit axis or extension of an amino acid side chain at the opposite, inner side, increased the subunit number from 11 to 12. Our findings are supported by crystal structures of TRAP oligomers and by native mass spectrometry data.The subunit number of the TRAP oligomer can be manipulated by introducing deletion or addition mutations at the subunit interface. An analysis of available and emerging structural data on alternative oligomeric states indicates that the same principles may also apply to the subunit number of other circular assemblies suggesting that the deletion/addition approach could be used generally to engineer transitions between different oligomeric states

APPLICATION OF INFORMATION SYSTEMS AND TOOLS IN BIOINFORMATICS

The pace at which scientific data is produced and disseminated has never been as high as it is currently. Modern sequencing technologies make it possible to obtain the genome of a specific organism in a few days, and the genome of a bacterial organism in less than a day, and therefore researchers from the field of life science are faced with a huge amount of data that needs to be analyzed. In this connection, various fields of science are converging with each other, giving rise to new disciplines. So, bioinformatics is one of these fields, it is a scientific discipline that has been actively developing over the past decades and uses IT tools and methods to solve problems related to the study of biological processes. In particular, a crucial role in the field of bioinformatics is played by the development of new algorithms, tools and the creation of new databases, as well as the integration of extremely large amounts of data. The rapid development of bioinformatics has made it possible to conduct modern biological research. Bioinformatics can help a biologist to extract valuable information from biological data by using tools to process them. Despite the fact that bioinformatics is a relatively new discipline, various web and computer tools already exist, most of which are freely available. This is a review article that provides an exhaustive overview of some of the tools for biological analysis available to a biologist, as well as describes the key role of information systems in this interdisciplinary field

Genetic diversity of Francisella tularensis subsp. holarctica in Kazakhstan

Tularemia is a highly dangerous zoonotic infection due to the bacteria Francisella tularensis. Low genetic diversity promoted the use of polymorphic tandem repeats (MLVA) as first-line assay for genetic description. Whole genome sequencing (WGS) is becoming increasingly accessible, opening the perspective of a time when WGS might become the universal genotyping assay. The main goal of this study was to describe F. tularensis strains circulating in Kazakhstan based on WGS data and develop a MLVA assay compatible with in vitro and in silico analysis. In vitro MLVA genotyping and WGS were performed for the vaccine strain and for 38 strains isolated in Kazakhstan from natural water bodies, ticks, rodents, carnivores, and from one migratory bird, an Isabellina wheatear captured in a rodent burrow. The two genotyping approaches were congruent and allowed to attribute all strains to two F. tularensis holarctica lineages, B.4 and B.12. The seven tandem repeats polymorphic in the investigated strain collection could be typed in a single multiplex PCR assay. Identical MLVA genotypes were produced by in vitro and in silico analysis, demonstrating full compatibility between the two approaches. The strains from Kazakhstan were compared to all publicly available WGS data of worldwide origin by whole genome SNP (wgSNP) analysis. Genotypes differing at a single SNP position were collected within a time interval of more than fifty years, from locations separated from each other by more than one thousand kilometers, supporting a role for migratory birds in the worldwide spread of the bacteria.Peer reviewe

Genetic diversity of Alternaria species associated with black point in wheat grains

The genus Alternaria is a widely distributed major plant pathogen that can act as a saprophyte in plant debris. Fungi of this genus frequently infect cereal crops and cause such diseases as black point and wheat leaf blight, which decrease the yield and quality of cereal products. A total of 25 Alternaria sp. isolates were collected from germ grains of various wheat cultivars from different geographic regions in Kazakhstan. We investigated the genetic relationships of the main Alternaria species related to black point disease of wheat in Kazakhstan, using the inter-primer binding site (iPBS) DNA profiling technique. We used 25 retrotransposon-based iPBS primers to identify the differences among and within Alternaria species populations, and analyzed the variation using clustering (UPGMA) and statistical approaches (AMOVA). Isolates of Alternaria species clustered into two main genetic groups, with species of A.alternata and A.tennuissima forming one cluster, and isolates of A. infectoria forming another. The genetic diversity found using retrotransposon profiles was strongly correlated with geographic data. Overall, the iPBS fingerprinting technique is highly informative and useful for the evaluation of genetic diversity and relationships of Alternaria species.Peer reviewe

New Pellet Feeds for Rabbits with a High Content of Nutrients and With the Addition of Dietary Supplements

This research presented the pellet feed production line. Three pellet feed formulasfor young stock rabbits (28-135 days old) were developed with the addition of experimental dietary supplements grouped into the following protein green complexes (PGC):PGC-92-1including thе following supplements- dried herbal pulp from red clover, herbal alfalfa meal, and Sporotherminprobiotic; PGC-92-2 including the following supplements - protein feed concentrate from wheat stillage filtrate (syrup), herbal alfalfa meal, and Sporothermin probiotic; PGC-92-3 including the following supplements – PGC from red clover, herbal alfalfa meal,andSporothermin probiotic. These were compared with feed formulated without dietary supplements (PGC-92 (Control)). The nutritional value of the concentrate feeds met the requirements assigned for this group of animals. The storage of the formulatedconcentrate feeds took place in industrial conditions (the floor store) in paper bags of 30 kg per group at the temperature of 18-20 ∘C and the relative humidity of 65-70%. Due to itsmoisture content exceeding the standard requirements, the check concentrate feed (Control) revealed a higher content of fungal and bacterial microflora. The fat acidityvalue and the total acidity increased, which indicated the instability of this batch of concentrate feed during storage. The experimental batches of concentrate feed had a stablequality and retained good quality throughout the testing period. The testing of the effects of the studied complexes in fattening young stock rabbits was carried out on the premises of the Lipetsk Rabbit LLC industrial complex with 2000 rabbits. The use ofall-in-onepellet feedsformulated with the addition ofdietary supplements made it possible to increase the slaughter yield by 3.62%, 4.45% and 3.96%, while reducing feed intake per 1 kg of slaughter mass by 0.72 ECU, 0.38 ECU and 0.88 ECU. There was an increase in profit of 17725.25rubles, 16114.38 rubles and 14168.55 rubles, and an increase in the level of profitability by 45.93%, 41.26% and 31.24%, which resulted from a highersafety andgrowth performance of the raised rabbits. Keywords: concentrate feeds, pellet feeds, dietary supplements, protein green complex, feed for rabbits, growth performanc