Please note that we have stopped the regular imports of Gene Expression Omnibus (GEO) data into ArrayExpress. This may not be the latest version of this experiment.
E-GEOD-34999 - The impact of Lactobacillus plantarum sortase on target-protein sorting, gastrointestinal persistence and host immunomodulation
Released on 12 January 2012, last updated on 4 May 2014
Sortases are transpeptidase enzymes that couple surface proteins to the peptidoglycan of Gram-positive bacteria. Several sortase-dependent proteins (SDPs) have been identified that are crucial for bacterial pathogenesis and, although less frequently, for the physiology of non-pathogenic bacteria. We found that an isogenic sortase A (srtA) deletion derivative (NZ7104) of Lactobacillus plantarum WCFS1 did not express any residual SrtA activity, i.e. failed to cleave the LPQTDE SrtA recognition motif. Trypsination of intact bacterial cells, followed by mass spectrometry based peptide identification, revealed a significant decrease, but not complete loss of SDPs on the NZ7104 cell surface as compared to the wildtype. Using LiCl, we further found that several SDPs could be extracted from the cell surface of NZ7104 but not from the wildtype, demonstrating that SrtA is involved in the covalent coupling of these SDPs. Neither the gastrointestinal persistence of L. plantarum in mice, nor the cytokine secretion patterns induced in monocyte derived immature dendritic cells (iDCs) was significantly affected by the srtA deletion. However, contrary to the wild-type cells, LiCl washed NZ7104 cells induced drastically increased proinflammatory cytokine production in iDCs, indicating a role of the SDPs in attenuation of immune system stimulation. array were constructed in two subdesigns: one comparing all samples from logarithmic phase (WT vs mutant) and one comparing the stationary phase samples (WT vs mutant)
transcription profiling by array
Michiel Wels <email@example.com>, Daniela M Remus, Michiel Kleerebezem, Peter A Bron, Roger S Bongers