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Updated: Jun 21, 2026
05:19
Isolation and Identification of Bacterial Strains from Skin of Terrestrial Amphibians
Published on: June 17, 2025
Hirschia maritima sp. nov., isolated from seawater
1Department of Science Education, Cheju National University, Jeju 690-756, Republic of Korea.
Summary
A novel orange-pigmented bacterium, Hirschia maritima sp. nov., was identified from seawater. This marine Alphaproteobacteria expands the known diversity within the Hirschia genus.
Area of Science:
- Microbiology
- Bacteriology
- Marine Biology
Background:
- The genus Hirschia comprises marine bacteria within the family Hyphomonadaceae.
- Understanding bacterial diversity in marine environments is crucial for ecological studies.
Purpose of the Study:
- To taxonomically characterize a novel bacterium isolated from seawater.
- To determine the phylogenetic and chemotaxonomic relationship of the isolate to existing species.
Main Methods:
- Polyphasic taxonomic approach including phenotypic, phylogenetic (16S rRNA gene sequencing), and chemotaxonomic analyses.
- DNA-DNA hybridization was performed to assess genomic relatedness.
- Cultivation under specific temperature and pH conditions.
Main Results:
- Strain GSW-2T is a Gram-negative, aerobic, orange-pigmented bacterium with prostheca and flagella.
- Phylogenetic analysis showed highest similarity (97.5%) to Hirschia baltica.
- Low DNA-DNA relatedness (8.8-13.6%) confirmed it as a distinct species.
- Chemotaxonomic data (fatty acids, quinones, DNA G+C content) supported its placement in the genus Hirschia.
Conclusions:
- Strain GSW-2T represents a new species, Hirschia maritima sp. nov.
- This finding expands the known species within the genus Hirschia.
- The bacterium's characteristics are consistent with a marine habitat.
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