Bacillus pallidus sp. nov., isolated from forest soil

Area of Science:

• Microbiology
• Bacterial Taxonomy
• Environmental Microbiology

Background:

• Soil microorganisms play crucial roles in ecosystem functions.
• The genus Bacillus comprises diverse Gram-positive bacteria with significant industrial and environmental relevance.
• Continuous discovery of novel bacterial species is essential for understanding microbial biodiversity.

Purpose of the Study:

• To isolate and characterize a novel bacterial strain from forest soil.
• To determine the taxonomic position of the novel strain using polyphasic methods.
• To propose a new species within the genus Bacillus.

Main Methods:

• Isolation and cultivation of bacteria from forest soil samples.
• Phenotypic characterization including morphology, growth conditions, and motility.
• Chemotaxonomic analysis involving fatty acid profiling and menaquinone determination.
• Molecular phylogenetic analysis based on 16S rRNA gene sequencing.
• Genomic DNA G+C content determination.

Main Results:

• A strictly aerobic, motile, rod-shaped, Gram-positive bacterium (strain CW 7(T)) was isolated.
• Optimal growth occurred at 30-37°C and pH 7.0-8.0.
• Chemotaxonomic data revealed anteiso-C15:0, iso-C15:0, and anteiso-C17:0 as major fatty acids, with MK-7 as the predominant menaquinone.
• Phylogenetic analysis placed strain CW 7(T) within the genus Bacillus, with <96.5% 16S rRNA gene sequence similarity to known species.
• The G+C content of the genomic DNA was 42.3 mol%.

Conclusions:

• Strain CW 7(T) represents a distinct lineage within the genus Bacillus.
• Based on comprehensive polyphasic taxonomic data, Bacillus pallidus sp. nov. is proposed as a new species.
• The type strain is CW 7(T) (=KCTC 13200(T)=CCTCC AB 207188(T)=LMG 24451(T)).