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Biological effects of Veillonella parvula and Bacteroides intermedius lipopolysaccharides
G Matera1, M C Liberto, M C Berlinghieri
1Istituto di Microbiologia, Facultà di Medicina e Chirurgia, Università di Reggio Calabria, Catanzaro, Italy.
Abstract:
A comparative study on the endotoxic effects of lipopolysaccharide (LPS) from Veillonella parvula ATCC 10790 and from Bacteroides intermedius BMH was performed using an in vivo approach in the C57BL/6 mouse. Phenol-water extracted LPS of such anaerobes was purified by ultracentrifugation and DNase/RNase digestion, and characterized by a metachromatic assay for endotoxins and by electrophoresis on SDS-polyacrylamide gel and silver staining. Mouse LD50 for V. parvula LPS was 1.479 mg and for B. intermedius greater than 3.160 mg. Sublethal amounts of the LPS from anaerobes as well as from facultative aerobes decreased daily water intake and body weight in the mouse. Endotoxin from Salmonella typhimurium SL1102, Escherichia coli 0128:B12 and V. parvula had a strong effect on water intake and body weight, whereas Bacteroides intermedius LPS activity was very weak. The results of the present report suggest that V. parvula LPS has a toxic in vivo activity on mouse, which is comparable to LPS from classic enteric organisms and stronger than B. intermedius LPS.
Insights
Veillonella parvula lipopolysaccharide (LPS) exhibits significant endotoxic effects in mice, comparable to common enteric bacteria. Bacteroides intermedius LPS showed much weaker toxicity in this in vivo study.
Area of Science:
- Microbiology
- Immunology
- Toxicology
Background:
- Lipopolysaccharide (LPS) is a major component of the outer membrane of Gram-negative bacteria.
- The endotoxic properties of LPS vary significantly between different bacterial species.
- Understanding LPS toxicity is crucial for managing infections and inflammatory responses.
Purpose of the Study:
- To comparatively analyze the in vivo endotoxic effects of lipopolysaccharide (LPS) from Veillonella parvula and Bacteroides intermedius.
- To assess the toxicity of anaerobic bacterial LPS in a mouse model.
Main Methods:
- Phenol-water extraction and purification of LPS from V. parvula and B. intermedius.
- Characterization using ultracentrifugation, DNase/RNase digestion, metachromatic assay, SDS-PAGE, and silver staining.
- In vivo toxicity assessment in C57BL/6 mice, including LD50 determination and observation of physiological changes.
Main Results:
- The median lethal dose (LD50) for V. parvula LPS was 1.479 mg, while for B. intermedius LPS it was greater than 3.160 mg.
- Sublethal doses of LPS from both anaerobes decreased water intake and body weight in mice.
- V. parvula LPS demonstrated strong endotoxic activity, comparable to LPS from Salmonella typhimurium and Escherichia coli, whereas B. intermedius LPS activity was weak.
Conclusions:
- Veillonella parvula LPS possesses significant in vivo toxicity in mice, similar to LPS from classical enteric bacteria.
- Bacteroides intermedius LPS exhibits considerably weaker endotoxic activity compared to V. parvula LPS.
- These findings highlight the variable endotoxic potential among anaerobic bacteria.