Mucilaginibacter segetis sp. nov., Isolated from Soil

Area of Science:

• Microbiology
• Bacterial Taxonomy
• Environmental Microbiology

Background:

• The genus Mucilaginibacter comprises bacteria found in diverse environments.
• Understanding bacterial diversity is crucial for ecological and biotechnological applications.

Purpose of the Study:

• To characterize a novel bacterial isolate from a soil sample collected on Dokdo Island, South Korea.
• To determine the taxonomic placement of the isolate within the Mucilaginibacter genus.

Main Methods:

• Isolation and cultivation of bacterial strain SD-g^T.
• Morphological, physiological, and biochemical characterization.
• 16S rRNA gene sequence analysis for phylogenetic identification.
• Genomic DNA G+C content determination.
• Chemotaxonomic analyses (respiratory quinone, polar lipids, fatty acids).
• Digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) calculations.

Main Results:

• Strain SD-g^T is a Gram-negative, short rod-shaped bacterium with pink colonies.
• Phylogenetic analysis based on 16S rRNA gene sequences placed the isolate within the genus Mucilaginibacter.
• Genomic DNA G+C content was 40.6 mol%.
• Chemotaxonomic data revealed MK-7 as the predominant respiratory quinone and phosphatidylethanolamine as the main polar lipid.
• Major fatty acids included summed feature 3, iso-C15:0, C16:0, and iso-C17:0 3-OH.
• Low dDDH (<18.4%) and ANI (<74.0%) values distinguished strain SD-g^T from closely related species.
• Strain SD-g^T exhibited distinct phenotypic and genotypic characteristics.

Conclusions:

• Strain SD-g^T represents a novel species within the genus Mucilaginibacter.
• The proposed name for this new species is Mucilaginibacter segetis sp. nov.
• The type strain is SD-g^T (KCTC 82353^T = JCM 34284^T).