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Updated: Aug 13, 2026
09:38
Physical Isolation of Endospores from Environmental Samples by Targeted Lysis of Vegetative Cells
Published on: January 21, 2016
Carotenoids present in halotolerant Bacillus spore formers
Le H Duc1, Paul D Fraser, Nguyen K M Tam
1School of Biological Sciences, Royal Holloway University of London, Egham, Surrey, UK.
FEMS Microbiology Letters
|February 2, 2006
Summary
Pigmented spore-forming bacteria found in Vietnamese faeces are closely related to Bacillus indicus. These bacteria produce yellow and orange carotenoid pigments, likely originating from seafood consumption.
Area of Science:
- Microbiology
- Bacterial Pigmentation
- Foodborne Bacteria
Background:
- Pigmented spore-forming bacteria were isolated from human faeces in Vietnam.
- The isolates showed characteristics similar to known pigmented Bacillus species.
Purpose of the Study:
- To identify and characterize pigmented spore-forming bacteria from human faeces.
- To investigate the origin and pigment composition of these bacterial isolates.
Main Methods:
- 16S rRNA gene sequencing for phylogenetic analysis.
- Growth tolerance assays (8% NaCl).
- High-performance liquid chromatography (HPLC) for pigment characterization.
Main Results:
- Six isolates were identified, closely related to Bacillus indicus.
- Isolates exhibited salt tolerance and arsenate resistance.
- Yellow carotenoid pigments were found in vegetative cells, and orange carotenoids in spores.
Conclusions:
- The bacteria are likely of seafood origin due to the Vietnamese diet and known habitats of similar species.
- The study characterizes novel bacterial pigments and their potential biosynthetic pathways.
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