Mesorhizobium koreense sp. nov., Isolated from Soil

Area of Science:

• Microbiology
• Bacteriology
• Taxonomy

Background:

• Soil harbors diverse microbial communities, including bacteria crucial for ecological processes.
• The genus Mesorhizobium comprises symbiotic bacteria known for nitrogen fixation, playing vital roles in agriculture and ecosystems.

Purpose of the Study:

• To isolate and characterize a novel bacterial strain from soil.
• To determine the taxonomic placement of the novel isolate using polyphasic characterization.

Main Methods:

• Isolation and cultivation of bacteria from soil samples.
• Gram staining, catalase testing, and morphological analysis.
• Phylogenetic analysis based on 16S rRNA gene sequences.
• Genomic analysis, including genome size and DNA G+C content determination.
• Fatty acid and polar lipid profiling.

Main Results:

• A novel aerobic, Gram-negative, rod-shaped, motile bacterium, strain WR6^T, was isolated.
• Phylogenetic analysis placed strain WR6^T within the genus Mesorhizobium, with 98.5% 16S rRNA gene sequence similarity to Mesorhizobium waimense.
• The genome size was 5,035,462 bp with a DNA G+C content of 62.6%.
• Unique chemotaxonomic features, including predominant fatty acids and polar lipids, were identified.

Conclusions:

• Strain WR6^T represents a novel species within the genus Mesorhizobium.
• The proposed name for this new species is Mesorhizobium koreense sp. nov.
• The type strain is WR6^T (=KCTC 92695^T =NBRC 116021^T).