Russian Academy of Sciences

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An extremely thermophilic chemolithoautotrophic strain Uz 6-8 was isolated from a hot spring in the Navoi region (Uzbekistan). Cells of strain Uz 6-8 were motile straight rods, non-spore-forming, 0.4–0.5 μm in diameter and 1.0−1.75 μm in length, with a gram-negative cell wall structure and a single lateral flagellum. The cells grew chemolithoautotrophically under aerobic conditions on thiosulfate or hydrogen in the medium containing NaHCO3, with CO2 in the gas phase. Nitrate was used as an electron acceptor during anaerobic growth on formate or hydrogen. The major fatty acids were saturated C18:0 and C20:0 with a cyclopropane moiety. The G+C content of the DNA was 47.5 mol %. Phylogenetic analysis based on comparison of 120 conserved proteins, DNA−DNA hybridization results (in silico), and genomic indices ANI and AAI indicated that Uz 6-8 belonged to a new species of the genus Pampinifervens (Aquificaceae). The name Pampinifervens navoyensis sp. nov. is proposed, with the type strain P. navoyensis Uz 6-8ᵀ. The genome contains the genes encoding the Arnon cycle, two uptake hydrogenases, and enzymes for formate oxidation, nitrate reduction, denitrification, and thiosulfate oxidation.

The aim of this study was to obtain culturable bacterial isolates, which are resistant to heat and salt stress, from saline soil samples enriched with plant residues, collected in the coastal zone of Lake Aydarkul (Uzbekistan). When all the 21 isolates, belonging to the family Bacillaceae, obtained in a cultivation medium with 60 g/L salinity, were tested for the ability to degrade plant polysaccharides, such as pectin and hemicellulose (xylan), the new isolate, Niallia sp. M35, was selected as the most interesting for application in plant residues hydrolysis under salt stress. The strain was actively growing on citrus pectin and birchwood xylan, degrading 46 ± 9 and 71 ± 5% of added polysaccharides, respectively. Genome sequencing revealed a very broad spectrum of carbohydrate-active enzymes (CAZymes), including 96 glycosyl hydrolases, as well as two extracellular polysaccharide lyases of families 8 and 11. Complete pathways of rhamnogalacturonan and xylan degradation were revealed in the M35 genome. Moreover, this isolate possessed the complete genomic potential for the mineralization of other polysaccharides. Overall, our data indicate that Niallia sp. M35 exhibits versatile metabolic and degradation potential useful not only for various biotechnological applications but also representing an important resource for the recycling of plant residues, thereby increasing the fertility of saline soils typically depleted in organic matter.

This study presents the results of a physiological and genomic analysis of the archaeal strain Acidiplasma sp. YE-1, a representative of extremely acidophilic, moderately thermophilic archaea of the family Ferroplasmaceae. This strain was dominant in a microbial community performing biooxidation of a pyrite–arsenopyrite gold-bearing concentrate. The strain is a moderately thermophilic extreme acidophile capable of oxidizing ferrous iron and sulfur, requiring an organic substrate in the medium for growth—characteristics typical of the genus Acidiplasma. Investigation of pyrite oxidation by Acidiplasma sp. YE-1 demonstrated that the strain oxidized pyrite in pure culture at a low rate, despite its ability to oxidize Fe2+ ions and sulfur. During pyrite bioleaching by a mixed culture of Acidiplasma sp. YE-1 and Acidithiobacillus caldus MBC-1, pyrite oxidation proceeded several times faster than in the respective pure cultures, which may indicate metabolic and physicochemical interactions between these microorganisms and the mineral. The mechanisms underlying these interactions require further study. A complete circular genome of Acidiplasma sp. YE-1 (GenBank accession number CP133599), 1 718 531 bp in length, was reconstructed—currently the only complete genome available for members of this genus. The genome contains a gene encoding sulfocyanin, a key electron transport chain protein involved in iron oxidation, as well as genes of sulfur-oxidizing enzymes, including sulfur oxygenase–reductase (SOR) and components of the cytoplasmic DsrE complex. Genes associated with the transport and catabolism of organic compounds and with the 3-hydroxypropionate/4-hydroxybutyrate carbon fixation cycle were also identified. The results provide a more detailed characterization of the genetic potential of this microorganism and allow comparative genomic analysis with previously described strains Acidiplasma aeolicum and Acidiplasma cupricumulans.

Introduction. Avian influenza virus (AIV) and Newcastle disease virus (NDV) pose serious threats to poultry health. Both pathogens are highly contagious and, due to their rapid spread, can lead to significant economic losses. Overlapping clinical signs complicate field differentiation of these diseases and delay response measures to isolate affected poultry. Rapid disease detection is critical for ensuring a timely response. Objective. To develop a user-friendly test kit for detection of AIV and paramyxoviruses in organ samples from sick and dead chickens during disease outbreaks in commercial poultry operations. Materials and methods. To differentiate AIV and paramyxoviruses in pathological samples collected from sick and dead birds, 96-well plates coated with fetuin and anti-NDV IgY in designated wells were used. The results obtained were compared with those from polymerase chain reaction (PCR) and virus titration in chicken embryos. Results. The developed method for pathogen detection is based on distinct virus-binding principles: influenza virus binds to a receptor analog, while paramyxoviruses bind to NDV specific antibodies. Previous studies using hundreds of strains have demonstrated that influenza A virus of various subtypes binds to the sialoglycosyl residues of bovine fetal serum protein – fetuin. In contrast, none of the paramyxovirus isolates tested bound to this sialoglycoprotein. For paramyxovirus capture, immunoglobulins isolated from the egg yolks of chickens immunized against NDV were utilized. Binding was performed in 96-well plates using a test-kit analogous to enzyme-linked immunosorbent assay (ELISA). Conclusion. The developed method enables the identification and differentiation of AIV and NDV in organ tissue homogenates from infected chickens within a few hours, representing a significant step toward preventing the spread and facilitating the eradication of dangerous disease outbreaks.