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OLIgo Mass Profiling (OLIMP) of Extracellular Polysaccharides
Published on: June 21, 2010
Expression of ropy and mucoid phenotypes in Lactococcus lactis
K P Dierksen1, W E Sandine, J E Trempy
1Department of Microbiology, Oregon State University, Corvallis 97331-3804, USA.
Journal of Dairy Science
|August 1, 1997
Summary
Environmental conditions influence the ropy phenotype in Lactococcus lactis. Ropy strains showed less Lon protease, suggesting its role in regulating polysaccharide production.
Area of Science:
- Microbiology
- Bacteriology
- Molecular Biology
Background:
- Lactococcus lactis strains exhibit diverse polysaccharide phenotypes, including ropy and mucoid.
- The expression of these phenotypes is inducible, suggesting the involvement of genetic regulators.
- Lon protease and RcsA are known regulators of polysaccharide expression in Escherichia coli.
Purpose of the Study:
- To determine environmental conditions for ropy phenotype expression in Lactococcus lactis.
- To investigate the presence and role of Lon protease and RcsA in lactococcal polysaccharide production.
Main Methods:
- Culturing Lactococcus lactis strains under various aerobic/anaerobic conditions and temperatures.
- Utilizing whey agar, Elliker agar, and M17L agar for growth.
- Employing Western blots to detect Lon protease and RcsA presence.
Main Results:
- Two Lactococcus lactis strains displayed inducible ropy and mucoid phenotypes.
- Evidence for structural conservation of Lon protease in lactococci was found.
- Ropy strains had lower levels of Lon-like protein compared to non-ropy strains.
Conclusions:
- Environmental factors modulate the ropy phenotype in Lactococcus lactis.
- Lon protease is structurally conserved in lactococci and may act as a negative regulator of polysaccharide expression.
- Further research is needed to elucidate the precise regulatory mechanisms.
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