Chitinophaga caeni sp. nov., isolated from activated sludge

Area of Science:

• Microbiology
• Bacteriology
• Environmental Science

Background:

• Activated sludge wastewater treatment plants are complex ecosystems harboring diverse microbial communities.
• The genus Chitinophaga, within the class Bacteroidetes, is known for its role in degrading chitin but remains incompletely characterized.
• Isolation and characterization of novel bacterial species are crucial for understanding microbial functions and developing biotechnological applications.

Purpose of the Study:

• To isolate and characterize a novel bacterial strain from an activated sludge sample.
• To determine the phylogenetic, chemotaxonomic, and genomic properties of the novel isolate.
• To propose a new species within the genus Chitinophaga based on comprehensive data.

Main Methods:

• Isolation of strain 13^T from activated sludge.
• 16S rRNA gene sequence analysis for phylogenetic placement.
• Chemotaxonomic analyses including cell wall composition, polar lipids, and fatty acids.
• Genome sequencing and analysis (5.28 Mb genome size, 42.5 mol% G+C content).

Main Results:

• Strain 13^T is a Gram-negative, non-motile, non-spore-forming, rod-shaped, strictly aerobic bacterium.
• Phylogenetic analysis indicated its closest relatives are Chitinophaga skermanii (92.4% similarity) and Chitinophaga rupis (91.2% similarity).
• Chemotaxonomic data revealed meso-diaminopimelic acid, ribose, phosphatidylethanolamine, iso-C15:0, C16:1ω5c, iso-C17:0 3-OH, and menaquinone-7.

Conclusions:

• Strain 13^T represents a novel species of the genus Chitinophaga.
• The proposed name for this novel species is Chitinophaga caeni sp. nov.
• The findings contribute to the understanding of bacterial diversity in wastewater treatment systems and the Chitinophaga genus.