Identification of bacterial isolates from soils of the Aral sea region.

Main Article Content

Ainura Smagulova

LLP «National Center for Biotechnology», Astana, Kazakhstan

smagulova@biocenter.kz

Vladimir Kiyan

LLP «National Center for Biotechnology», Astana, Kazakhstan

vskiyan@gmail.com

Rabiga Uakhit

LLP «National Center for Biotechnology», Astana, Kazakhstan

erken.uakhitrabiga@gmail.com

Shuga Manabayeva

LLP «National Center for Biotechnology», Astana, Kazakhstan

manabayeva@biocenter.kz

Abstract

The Aral Sea region is an extreme arid-saline environment formed under long-term desiccation, salinization, and degradation of coastal and former seabed soils. The aim of this study was to perform the molecular genetics and taxonomic identification of culturable bacterial isolates recovered from soils of the Aral Sea region. Soil samples were collected from 9 sampling sites located in the coastal zone adjacent to the dried Aral seabed. A total of 42 bacterial isolates were obtained, characterized by colony morphology and microscopy, and identified by 16S rRNA gene sequencing followed by phylogenetic analysis in MEGA11. The isolates were assigned to 23 species belonging to 11 genera, including Priestia, Bacillus, Planomicrobium, Paenibacillus, Streptomyces, Microbacterium, Sphingobium, Sphingomonas, Pseudomonas, Acinetobacter, and Acidovorax. The species distribution was uneven, with the predominance of Paenibacillus, Bacillus, and Pseudomonas. Among the most frequent taxa were Paenibacillus xylanexedens, Paenibacillus barcinonensis, Bacillus subtilis, and Pseudomonas putida. Phylogenetic reconstruction based on 24 nucleotide sequences and 604 aligned positions confirmed clustering according to taxonomic affiliation. The obtained results demonstrate substantial taxonomic heterogeneity of culturable bacteria in Aral Sea soils and provide a basis for further studies of their ecological roles and biotechnological potential.

Keywords:
soil, Aral Sea, salt tolerance, bacteria, microbiome

Article Details

Received 2026-04-13
Accepted 2026-05-06
Published 2026-06-27

References

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