bioRxiv Science⌕ Search

Biology subjects

Rastorguev, S. M.

Publications and source records attributed to Rastorguev, S. M..

2 recordsLinked to original sources
bioRxiv2026

Vibrio aquamarinus sp. nov., a luminous marine bacteria isolated from the Black Sea Vibrio aquamarinus sp. nov., a luminous marine bacteria isolated from the Black Sea

Three novel bioluminescent bacterial strains, VNB-15T, VNB-16 and SChm4, were isolated from water of the Black Sea (Russia) and intestines of the Black Sea horse mackerel. Cells of the isolated strains are motile Gram negative slightly curved rods with single polar flagellum. The temperature range for growth was 10-35{degrees}C, the optimum being 20-25{degrees}C. The pH range for growth was 6.0-9.0, the optimum being 7.0-8.0. The bacteria were able to grow in the presence of 0.5 to 5.0% NaCl (w/v), the optimum being 1.0-4.0% (w/v). Phylogenetic analysis based on comparison of 16S rRNA sequences shows these strains to have kinship with the species Vibrio jasicida, Vibrio hyugaensis, Vibrio alginolyticus, Vibrio campbelli, Vibrio rotiferianus, Vibrio harveyi and Vibrio owensii with sequence similarity from 99.6 to 98.0%. Phylogenetic analysis based on comparison of the sequences of genes gyrB, recA, pyrH, gapA, rpoA, mreB, ftsZ, topA shows that the strains VNB-15T, VNB-16 and SChm4 to form a cluster within the V. harveyi clade and belong to a new species of the Vibrio genus. Comparison of the complete genomic sequence of VNB-15T with typical strains of nearby species also indicates that VNB-15T belongs to a separate species (maximum similarity 98% with V. hyugaensis and 96% with V. jasicida). VNB-15T differs from closely related species by its ability to utilize glucose, mannitol, inositol, sorbitol, rhamnose and sucrose, and to form lysine decarboxylase, ornithine decarboxylase, lipase, acid phosphatase, -glucosidase, {beta}-glucosidase and N-acetyl-{beta}-D-glucosaminidase enzymes. Based on phylogenetic analysis and phenotypic characteristics, Vibrio aquamarinus sp. nov. is proposed. The type strain is VNB-15T (= VKPM B-11245T = DSM 26054 T). RepositoriesThe GenBank accession numbers for the gapA, 16S rRNA, gyrB, pyrH, rpoA, recA, mreB, ftsZ, topA genes sequences of strain VNB-15T are JQ319116-JQ319121, KX242381, KX 242384, KX242387, respectively. The GenBank accession numbers for the gapA, gyrB, pyrH, recA, rpoA,16S rRNA, mreB, ftsZ, topA genes sequences of strain VNB-16 are KP221561-KP221566, KX242382, KX 242385, KX242388 respectively. The GenBank accession numbers for the 16S rRNA, gapA gyrB, rpoA, recA, pyrH, mreB, ftsZ, topA genes sequences of strain SChm4 are KX242375-KX242380, KX242383, KX 242386, KX242389, respectively. The GenBank/EMBL/DDBJ accession numbers for the housekeeping gene sequences used in this study are detailed in supplementary Table S1, Figures S1-S8. The genome of Vibrio aquamarinus sp. nov. VNB-15T, comprising two chromosomes and a plasmid, has been assembled and deposited in the NCBI database under the submission number SUB14585067

molecular biology↗
bioRxiv2025

A new family of small ArdA proteins reveals an antirestriction activity.

Antirestriction proteins are known to protect mobile genetic elements from the hosts restriction-modification (RM) systems. In our study, we identified a new family of small proteins, which we named sArdA The sArdA proteins are homologous to DNA-mimicking ArdA proteins but differ in size, being approximately one-third the length of full ArdAs. Moreover, sArdA family contains two subgroups, one of which is structurally similar to the N-terminal end of ArdA, while the other one - to the C-terminal end. Phylogenetic analysis demonstrated that genes encoding these proteins evolved into evolutionarily stable subfamilies, named sArdN and sArdC, respectively. Alphafold structure prediction of sArdA interaction with RM systems revealed four states of EcoKI, which differ the angle between its two M-subunits while interacting with different agents. Interestingly, both sArdN and sArdC triggered the same intermediate closed state of EcoKI indicating the possible new interaction pathways of Ards with RM systems. For phenotypic studies in Escherichia coli cells, we cloned the sardN gene from the chromosome of Corynebacterium pilbarense and the sardC gene from Lactococcus cremoris. Both genes were shown to protect {lambda} phage DNA from restriction by the type I RM system. However, they revealed specificity to different restriction-modification systems. Specifically, sArdC was more effective against EcoR124II, whereas sArdN was more potent against EcoKI. Furthermore, both genes demonstrated high antimethylation activity against EcoKI. Our current findings suggest the idea that binding specificity of DNA-mimicking proteins to their targets could also be achieved by very short proteins.

molecular biology↗