Paenibacillus caseinilyticus sp. nov., isolated forest soil

Area of Science:

• Microbiology
• Bacteriology
• Taxonomy

Background:

• Forest soil harbors diverse microbial communities.
• The genus Paenibacillus is known for its ecological roles and biotechnological potential.
• Accurate bacterial classification is crucial for understanding microbial diversity and function.

Purpose of the Study:

• To isolate and characterize a novel bacterial strain from forest soil.
• To determine the phylogenetic and taxonomic position of the novel strain.
• To propose a new species within the Paenibacillus genus based on comprehensive analysis.

Main Methods:

• Isolation and cultivation of bacterial strain GW78T from forest soil.
• Phenotypic characterization including Gram staining, motility, and growth conditions.
• Phylogenetic analysis using 16S rRNA gene sequencing.
• Chemotaxonomic analysis of menaquinone, polar lipids, and fatty acids.
• Genomic analysis including Digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI).

Main Results:

• Strain GW78T is a milky-white-coloured, aerobic, Gram-positive, rod-shaped, and motile bacterium.
• Optimal growth at 37°C and pH 7.0; catalase-positive and oxidase-negative.
• 16S rRNA gene sequence analysis showed 98.3% similarity to Paenibacillus mucilaginosus.
• Chemotaxonomic data revealed MK-7, specific polar lipids, and predominant fatty acids.
• dDDH and ANI values were below 74.0% and 14.0% respectively, differentiating it from related species.

Conclusions:

• Strain GW78T represents a novel species of the genus Paenibacillus.
• The proposed name for the novel species is Paenibacillus caseinilyticus sp. nov.
• The type strain is GW78T, with accession numbers KCTC 43430T and NBRC 116023T.