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Updated: May 8, 2026
11:07
In Situ Isolation and Culturing of Recalcitrant Soil Bacteria using an Isolation Chip (iChip)
Published on: August 6, 2025
Acinetobacter kookii sp. nov., isolated from soil.
Ji Young Choi1, Gwangpyo Ko2, Weonghwa Jheong3
1Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon 440-746, Republic of Korea.
Summary
Six novel bacterial strains from diverse global soil and sediment samples represent a new species, Acinetobacter kookii. This discovery expands the known diversity within the Acinetobacter genus.
Area of Science:
- Microbiology
- Bacterial Taxonomy
- Environmental Microbiology
Background:
- The genus Acinetobacter comprises diverse Gram-negative, non-fermentative bacteria found in various environments.
- Accurate taxonomic classification is crucial for understanding microbial roles and interactions.
Purpose of the Study:
- To characterize and classify six novel bacterial isolates from South Korea, Germany, the Netherlands, Malaysia, and Thailand.
- To determine if these isolates represent a new species within the Acinetobacter genus.
Main Methods:
- Phylogenetic analysis using 16S rRNA, rpoB, and gyrB gene sequences.
- DNA-DNA reassociation assays to assess genetic relatedness.
- Analysis of carbon source utilization and cellular fatty acid profiles.
Main Results:
- The six strains formed a distinct phylogenetic cluster within the Acinetobacter genus, showing highest 16S rRNA gene similarity to Acinetobacter beijerinckii.
- Low DNA-DNA reassociation values (<40%) confirmed their status as a novel species.
- Distinctive utilization of azelate, 2,3-butanediol, ethanol, and dl-lactate was observed.
- Cellular fatty acid profiles were consistent with related Acinetobacter species.
Conclusions:
- The six strains represent a novel species, Acinetobacter kookii sp. nov.
- The proposed type strain is 11-0202(T).
- This finding contributes to the understanding of Acinetobacter diversity in environmental samples.
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