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Flavobacterium croceum sp. nov., isolated from activated sludge
Minjeong Park1, Shipeng Lu1, Seung Hyun Ryu1
1Division of Applied Life Science, EB-NCRC, PMBBRC, Gyeongsang National University, Jinju 660-701, Republic of Korea.
Summary
A novel bacterium, Flavobacterium croceum, was discovered in wastewater treatment sludge. This Gram-negative bacterium exhibits unique fatty acid profiles and represents a new species within the Flavobacterium genus.
Area of Science:
- Microbiology
- Environmental Science
- Wastewater Treatment
Background:
- Enhanced biological phosphorus removal (EBPR) is crucial for wastewater treatment.
- Microbial communities in EBPR systems are complex and harbor diverse bacterial species.
- Understanding bacterial diversity aids in optimizing wastewater treatment processes.
Purpose of the Study:
- To isolate and characterize a novel bacterial strain from activated sludge involved in EBPR.
- To determine the taxonomic placement of the novel isolate within the genus Flavobacterium.
- To propose a new species name based on comprehensive phenotypic, chemotaxonomic, and molecular data.
Main Methods:
- Isolation of bacteria from activated sludge in a sequencing batch reactor.
- Determination of optimal growth conditions (temperature, pH).
- Analysis of cellular fatty acid composition and polar lipid profiles.
- Genomic DNA G+C content determination and major quinone analysis.
- 16S rRNA gene sequence analysis for phylogenetic placement.
Main Results:
- A Gram-negative, non-motile, rod-shaped bacterium, strain EMB47(T), was isolated.
- Optimal growth occurred at 25-35°C and pH 7.5-8.0.
- Distinct fatty acid and polar lipid profiles were identified.
- 16S rRNA gene sequence similarity to known Flavobacterium species was below 94.7%.
- Genomic DNA G+C content was 40.8 mol% with MK-6 as the major quinone.
Conclusions:
- Strain EMB47(T) represents a novel species within the genus Flavobacterium.
- The proposed name for this new species is Flavobacterium croceum sp. nov.
- This discovery contributes to the understanding of microbial diversity in wastewater treatment systems.
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