Haloalkane-utilizing Rhodococcus strains isolated from geographically distinct locations possess a highly conserved gene cluster encoding haloalkane catabolism

The sequences of the 16S rRNA and haloalkane dehalogenase (dhaA) genes of five gram-positive haloalkane-utilizing bacteria isolated from contaminated sites in Europe, Japan, and the United States and of the archetypal haloalkane-degrading bacterium Rhodococcus sp. strain NCIMB13064 were compared. The 16S rRNA gene sequences showed less than 1% sequence divergence, and all haloalkane degraders clearly belonged to the genus Rhodococcus. All strains shared a completely conserved dhaA gene, suggesting that the dhaA genes were recently derived from a common ancestor. The genetic organization of the dhaA gene region in each of the haloalkane degraders was examined by hybridization analysis and DNA sequencing. Three different groups could be defined on the basis of the extent of the conserved dhaA segment. The minimal structure present in all strains consisted of a conserved region of 12.5 kb, which included the haloalkane-degradative gene cluster that was previously found in strain NCIMB13064. Plasmids of different sizes were found in all strains. Southern hybridization analysis with a dhaA gene probe suggested that all haloalkane degraders carry the dhaA gene region both on the chromosome and on a plasmid (70 to 100 kb). This suggests that an ancestral plasmid was transferred between these Rhodococcus strains and subsequently has undergone insertions or deletions. In addition, transposition events and/or plasmid integration may be responsible for positioning the dhaA gene region on the chromosome. The data suggest that the haloalkane dehalogenase gene regions of these gram-positive haloalkane-utilizing bacteria are composed of a single catabolic gene cluster that was recently distributed world-wide

Modular approach to select bacteriophages targeting Pseudomonas aeruginosa for their application to children suffering with cystic fibrosis

This review discusses the potential application of bacterial viruses (phage therapy) towards the eradication of antibiotic resistant Pseudomonas aeruginosa in children with cystic fibrosis (CF). In this regard, several potential relationships between bacteria and their bacteriophages are considered. The most important aspect that must be addressed with respect to phage therapy of bacterial infections in the lungs of CF patients is in ensuring the continuity of treatment in light of the continual occurrence of resistant bacteria. This depends on the ability to rapidly select phages exhibiting an enhanced spectrum of lytic activity among several well-studied phage groups of proven safety. We propose a modular based approach, utilizing both mono-species and hetero-species phage mixtures. With an approach involving the visual recognition of characteristics exhibited by phages of well-studied phage groups on lawns of the standard P. aeruginosa PAO1 strain, the simple and rapid enhancement of the lytic spectrum of cocktails is permitted, allowing the development of tailored preparations for patients capable of circumventing problems associated with phage resistant bacterial mutants

Rational design of a (S)-selective-transaminase for asymmetric synthesis of (1S)-1-(1,1′-biphenyl-2-yl)ethanamine

Amine transaminases offer an environmentally sustainable synthesis route for the production of pure chiral amines. However, their catalytic efficiency toward bulky ketone substrates is greatly limited by steric hindrance and therefore presents a great challenge for industrial synthetic applications. We hereby report an example of rational transaminase enzyme design to help alleviate these challenges. Starting from the Vibrio fluvialis amine transaminase that has no detectable catalytic activity toward the bulky aromatic ketone 2-acetylbiphenyl, we employed a rational design strategy combining in silico and in vitro studies to engineer the transaminase enzyme with a minimal number of mutations, achieving an high catalytic activity and high enantioselectivity. We found that, by introducing two mutations W57G/R415A, detectable enzyme activity was achieved. The rationally designed variant, W57F/R88H/V153S/K163F/I259M/R415A/V422A, showed an improvement in reaction rate by more than 1716-fold toward the bulky ketone under study, producing the corresponding enantiomeric pure (S)-amine (enantiomeric excess (ee) value of >99%)

Phenotypic and genotypic variations within a single bacteriophage species

<p>Abstract</p> <p>Background</p> <p>Although horizontal gene transfer plays a pivotal role in bacteriophage evolution, many lytic phage genomes are clearly shaped by vertical evolution. We investigated the influence of minor genomic deletions and insertions on various phage-related phenotypic and serological properties.</p> <p>Findings</p> <p>We collected ten different isolates of <it>Pseudomonas aeruginosa </it>bacteriophage ϕKMV. All sequenced genomes (42-43 kb, long direct terminal repeats) are nearly identical, which intuitively implied strongly similar infections cycles. However, their latent periods vary between 21 and 28 minutes and they are able to lyse between 5 and 58% of a collection of 107 clinical <it>P. aeruginosa </it>strains. We also noted that phages with identical tail structures displayed profound differences in host spectra. Moreover, point mutations in tail and spike proteins were sufficient to evade neutralization by two phage-specific antisera, isolated from rabbits.</p> <p>Conclusion</p> <p>Although all analyzed phages are 83-97% identical at the genome level, they display a surprisingly large variation in various phenotypic properties. The small overlap in host spectrum and their ability to readily escape immune defences against a nearly identical phage are promising elements for the application of these phages in phage therapy.</p

Metagenomic characterisation of the viral community of lough neagh, the largest freshwater lake in Ireland

Lough Neagh is the largest and the most economically important lake in Ireland. It is also one of the most nutrient rich amongst the world's major lakes. In this study, 16S rRNA analysis of total metagenomic DNA from the water column of Lough Neagh has revealed a high proportion of Cyanobacteria and low levels of Actinobacteria, Acidobacteria, Chloroflexi, and Firmicutes. The planktonic virome of Lough Neagh has been sequenced and 2,298,791 2×300 bp Illumina reads analysed. Comparison with previously characterised lakes demonstrates that the Lough Neagh viral community has the highest level of sequence diversity. Only about 15% of reads had homologs in the RefSeq database and tailed bacteriophages (Caudovirales) were identified as a major grouping. Within the Caudovirales, the Podoviridae and Siphoviridae were the two most dominant families (34.3% and 32.8% of the reads with sequence homology to the RefSeq database), while ssDNA bacteriophages constituted less than 1% of the virome. Putative cyanophages were found to be abundant. 66,450 viral contigs were assembled with the largest one being 58,805 bp; its existence, and that of another 34,467 bp contig, in the water column was confirmed. Analysis of the contigs confirmed the high abundance of cyanophages in the water column

Analysis and generalization of the manifestation of different types of force in competitive exercises of the leaders of the world armwrestling weighing over 100 kg

Purpose: approbation of a complex of speed-strength characteristics for monitoring the dynamics of strength exercises of the world’s leading armwrestlers weighing over 100 kg. Material and Methods. The study involved the 3 best arm wrestlers in the world weighing over 100 kg (116.00 ± 18.03 kg) in 2017–2020. Four power test exercises have been identified that ensure the performance of a competitive action in arm wrestling: flexion of the fingers, stretch with a hammer, hook and bending the hand. These exercises were performed with the left and right hands. Strength indicators in all test exercises were measured with an FL1K 0.5N, 1000N electric strain gauge dynamometer, Kern & Sohn GmbH (China) with an accuracy class of up to 50 g, fixed on a specialized armwrestling table using a specially made an author’s block device. In the course of statistical analysis, the following parameters were determined and calculated: maximum (F) and relative (F1 = ƩF / m) strength, kg; total strength index in four strength exercises (ƩF = F1 + F2 + F3 + F4), kg; time to reach maximum strength (Ʃt = t1 + t2 + t3 + t4), s; speed-strength index (J = ƩF / Ʃt), kg/ms; average strength, index of four exercises ( = ƩF / 4), kg; total strength gradient of four exercises (Ʃt0,5F), ms; speed-strength index in the first 500 ms (J500 = ƩF500 / Ʃt500), kg/ms; time to reach 1 kg force (t1 = Ʃt0.5F / (0.5×F)), ms/kg; Pearson’s correlation analysis; Factor analysis. Results. As a result of the study, the main data on the speed-strength indicators of armwrestlers were obtained and analyzed. In the process of testing, according to the indicators of time periods and these efforts of dynamic strength, the features of the manifestation of explosive, fast and slow strength of arm wrestlers weighing over 100 kg were established. Determining the relationship between strength and speed-strength indicators using factor analysis made it possible to establish two factors that determine the overall variance of the sample. The first factor with a contribution of 70.9 % to the total sample formed the temporal characteristics of effort in test exercises, such as the time to reach maximum effort (r = 0.979), speed-strength index (r = 0.986), force gradient. (r = 0.986) and the time to reach a force of 1 kg (r = 0.979). The second factor with a factor loading of 29.1 % was the maximum force (r = 0.960), the average test strength (r = 0.961) and the achieved force in 500 ms (r = 0.716). Thus, the results of the correlation and factorial analyzes of the strength and speed-strength indicators of armwrestlers weighing more than 100 kg indicate the priority of the temporal characteristics of efforts over strength in a competitive exercise. Conclusions. The study made it possible to test a complex of speed-strength indicators for monitoring the functional state of the world’s leading armwrestlers weighing over 100 kg, an approved system of criteria for time and power characteristics of efforts in competitive exercises allows you to monitor the state of athletes to monitor and predict success in armwrestling. The author’s device used in the study made it possible to automate the process of measurements with high mobility, as well as immediately create a database on the power and speed-strength capabilities of armwrestlers with high accuracy

Comparative Analysis of the Efforts of Highly Qualified Elite Armwrestlers with Different Strength Abilities

Study purpose. Determination of the peculiarities of the manifestation of strength in competitive exercises of highly qualified armwrestlers with different strength abilities. Materials and methods. The study involved the 4 best armwrestlers in the world weighing from 80 to 100 kg (m = 87.50 ± 2.47 kg) in 2017–2020. Four power test exercises have been identified that ensure the performance of a competitive action in armwrestling: flexion of the fingers, stretch with a hammer, hook and bending the hand. Strength indicators in all test exercises were measured with an FL1K 0.5N, 1000N electric strain gauge dynamometer, Kern & Sohn GmbH (China), fixed on the armwrestling table using an author’s block device. Results. The results of the correlation analysis of the relationships between the studied indicators confirm the presence of a difference in the direction and strength of the relationships between the strength and time characteristics of the efforts of athletes with different strength and speed-strength abilities. Thus, out of 36 correlation indicators, the data of armwrestlers 1 and 2 have 11 modules with very high connection strength (r = 0.926–0.999), of which 7 modules are with time and 4 modules are with force characteristics of efforts. Athletes 3 and 4 also have 3 modules with very strong connections (r = 0.916–0.948) and 8 modules with strong connections (r = 0.739–0.886), of which 7 modules are with strength indicators and 4 modules are related to time characteristics. But the other correlation indicators have very weak (r < 0.29) and weak (r = 0.3–0.5) levels of relationships. Conclusions. Analysis of the time and force characteristics of the manifestation of force in the process of achieving boundary resistance allows us to clearly establish the genetically determined speed and strength abilities of the explosive, fast and slow force of armwrestlers

Механізми реалізації потенціалу дематеріалізації та ресурсозбереження національної економіки в умовах інформаційного суспільства

У звіті здійснено теоретичне обгрунтування передумов формування і реалізації потенціалу дематеріалізації та ресурсозбереження національної економіки. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/3555

Механізми реалізації потенціалу дематеріалізації та ресурсозбереження національної економіки в умовах інформаційного суспільства

У звіті здійснено теоретичне обгрунтування передумов формування і реалізації потенціалу дематеріалізації та ресурсозбереження національної економіки. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/3555