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Functionality of sortase A in Lactococcus lactis
Yakhya Dieye1, Virginie Oxaran, Florence Ledue-Clier
1INRA, UMR1319 Micalis, Domaine de Vilvert, F-78352 Jouy-en-Josas, France.
Applied and Environmental Microbiology
|September 21, 2010
Summary
Lactococcus lactis sortase A (SrtA) anchors five LPXTG substrates to the cell wall. This study suggests SrtA functions as the primary housekeeping sortase in L. lactis IL1403.
Area of Science:
- Microbiology
- Molecular Biology
- Bacteriology
Background:
- Sortases are essential bacterial enzymes involved in cell wall anchoring.
- Lactococcus lactis is a key lactic acid bacterium used in food fermentation.
- The specific role of sortases in L. lactis has not been fully elucidated.
Purpose of the Study:
- To investigate the functionality of the putative sortase A (SrtA) in Lactococcus lactis IL1403.
- To determine if SrtA is responsible for anchoring LPXTG-containing substrates to the bacterial cell wall.
Main Methods:
- Bioinformatic analysis to identify sortase A and its putative substrates.
- Experimental validation of SrtA activity on selected LPXTG substrates.
- Cell wall fractionation and protein analysis.
Main Results:
- Lactococcus lactis IL1403 possesses a sortase A (SrtA) and 11 putative sortase substrates.
- SrtA was confirmed to anchor five LPXTG substrates to the cell wall.
- Evidence supports SrtA's role in anchoring surface proteins in L. lactis.
Conclusions:
- Sortase A (SrtA) is functionally active in Lactococcus lactis IL1403.
- SrtA plays a crucial role in anchoring LPXTG-motif proteins to the cell wall.
- SrtA is likely the housekeeping sortase responsible for essential cell wall anchoring in L. lactis.
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