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Despite benefits such as lower water and working volume requirements, thermophilic high solids anaerobic digestion (THSAD) often fails due to the rapid build-up of volatile fatty acids (VFAs) and the associated drop in pH. Use of conductive materials (CM) can promote THSAD through stimulation of direct interspecies electron transfer (DIET), while the need for their constant dosing due to poor separation from effluent impairs economic feasibility. This study used an approach of spatially separating magnetite and granular activated carbon (GAC) from the organic fraction of municipal solid waste (OFMSW) in a single reactor for THSAD. GAC and magnetite addition could both mitigate the severe inhibition of methanogenesis after VFAs build-up to ∼28-30 g/L, while negligible methane production was observed in the control group. The highest methane yield (286 mL CH 4 /g volatile solids (VS)) was achieved in magnetite-added reactors, while the highest maximum CH 4 production rates (26.38 mL CH 4 /g VS/d) and lowest lag-phase (2.83 days) were obtained in GAC-added reactors. The enrichment of GAC and magnetite biofilms with various syntrophic and potentially electroactive microbial groups (Ruminiclostridium 1, Clostridia MBA03, Defluviitoga, Lentimicrobiaceae) in different relative abundances indicates the existence of specific preferences of these groups for the nature of CM. According to predicted basic metabolic functions, CM can enhance cellular processes and signals, lipid transport and metabolism, and methane metabolism, resulting in improved methane production. Rearrangement of metabolic pathways, formation of pili-like structures, enrichment of biofilms with electroactive groups and a significant improvement in THSAD performance was attributed to the enhancement of the DIET pathway. Promising results obtained in this work due to the spatial separation of the bulk OFMSW and CM can be useful for modeling larger-scale THSAD systems with better recovery of CM and cost-effectiveness., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Plague is a highly dangerous vector-borne infectious disease that has left a significant mark on history of humankind. There are 13 natural plague foci in the Caucasus, located on the territory of the Russian Federation, Azerbaijan, Armenia and Georgia. We performed whole-genome sequencing of Y. pestis strains, isolated in the natural foci of the Caucasus and Transcaucasia. Using the data of whole-genome SNP analysis and Bayesian phylogeny methods, we carried out an evolutionary-phylogeographic analysis of modern population of the plague pathogen in order to determine the phylogenetic relationships of Y. pestis strains from the Caucasus with the strains from other countries., Results: We used 345 Y. pestis genomes to construct a global evolutionary phylogenetic reconstruction of species based on whole-genome SNP analysis. The genomes of 16 isolates were sequenced in this study, the remaining 329 genomes were obtained from the GenBank database. Analysis of the core genome revealed 3315 SNPs that allow differentiation of strains. The evolutionary phylogeographic analysis showed that the studied Y. pestis strains belong to the genetic lineages 0.PE2, 2.MED0, and 2.MED1. It was shown that the Y. pestis strains isolated on the territory of the East Caucasian high-mountain, the Transcaucasian high-mountain and the Priaraksinsky low-mountain plague foci belong to the most ancient of all existing genetic lineages - 0.PE2., Conclusions: On the basis of the whole-genome SNP analysis of 345 Y. pestis strains, we describe the modern population structure of the plague pathogen and specify the place of the strains isolated in the natural foci of the Caucasus and Transcaucasia in the structure of the global population of Y. pestis. As a result of the retrospective evolutionary-phylogeographic analysis of the current population of the pathogen, we determined the probable time frame of the divergence of the genetic lineages of Y. pestis, as well as suggested the possible paths of the historical spread of the plague pathogen., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Bacillus anthracis is a pathogenic bacterium, which causes anthrax disease. The ability of this bacterium to form spores, which can be preserved in soil for decades and cause outbreaks later on, makes this pathogen a serious problem for veterinary and health services of many countries. Siberia is one of the most anthrax-influenced regions of Russia. In this research we report on the results of genotyping based on whole genome SNP analysis of 15 strains, isolated on the territory of Eastern Siberia and the Far East in 1956-2018. In this research, we sequenced 15 genomes of B. anthracis strains isolated from infected humans and animals, and from soil samples from the territory of Eastern Siberia and the Far East in the period from 1956 to 2018. We used genomic sequences obtained in this study and 219 B. anthracis genomes available in the international GenBank database to perform a comparative analysis. As a result we detected 6400 chromosomal SNPs which allowed to differentiate the studied strains. We built phylogenetic reconstruction of the global B. anthracis population based on the detected SNPs using the Maximum Likelihood Method and described genetic diversity of the strains isolated on the territory of Eastern Siberia and the Far East. Strains, isolated on this territory from 1956 to 2018 belong to 5 different genetic groups: "Ames", "STI", "Tsiankovskii", "Siberia" and "Asia". The greatest diversity of the strains is registered for two regions of the southern part of Eastern Siberia - Tyva and Buryatia. This research expands current understanding of genetic diversity of B. anthracis strains circulating on the territory of Russia., (Copyright © 2021 Elsevier Inc. All rights reserved.)