Proteomic and Transcriptomic Profiling of Staphylococcus aureus Surface LPXTG-proteins: Correlation with agr Genotypes and Adherence Phenotypes
| Autor: | Paul Majcherczyk, Philippe Moreillon, Mathilde Ythier, Alexandre Panchaud, Grégory Resch, Aurélie Gfeller, Patrice Waridel, Manfredo Quadroni |
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| Rok vydání: | 2012 |
| Předmět: |
Proteomics
Staphylococcus aureus Genotype Iron Protein domain medicine.disease_cause Biochemistry Bacterial Adhesion Analytical Chemistry Microbiology chemistry.chemical_compound Bacterial Proteins Peptide Library Lactococcus medicine Trypsin RNA Messenger Databases Protein Molecular Biology Microbial Viability biology Gene Expression Profiling Research Lactococcus lactis Membrane Proteins Gene Expression Regulation Bacterial biology.organism_classification Bacterial adhesin Kinetics Phenotype chemistry Mutation biology.protein Peptidoglycan DNA microarray Peptides Protein A |
| Zdroj: | Molecular & Cellular Proteomics. 11:1123-1139 |
| ISSN: | 1535-9476 |
| DOI: | 10.1074/mcp.m111.014191 |
| Popis: | Staphylococcus aureus infections involve numerous adhesins and toxins, which expression depends on complex regulatory networks. Adhesins include a family of surface proteins covalently attached to the peptidoglycan via a conserved LPXTG motif. Here we determined the protein and mRNA expression of LPXTG-proteins of S. aureus Newman in time-course experiments, and their relation to fibrinogen adherence in vitro. Experiments were performed with mutants in the global accessory-gene regulator (agr), surface protein A (Spa), and fibrinogen-binding protein A (ClfA), as well as during growth in iron-rich or iron-poor media. Surface proteins were recovered by trypsin-shaving of live bacteria. Released peptides were analyzed by liquid chromatography coupled to tandem mass-spectrometry. To unambiguously identify peptides unique to LPXTG-proteins, the analytical conditions were refined using a reference library of S. aureus LPXTG-proteins heterogeneously expressed in surrogate Lactococcus lactis. Transcriptomes were determined by microarrays. Sixteen of the 18 LPXTG-proteins present in S. aureus Newman were detected by proteomics. Nine LPXTG-proteins showed a bell-shape agr-like expression that was abrogated in agr-negative mutants including Spa, fibronectin-binding protein A (FnBPA), ClfA, iron-binding IsdA, and IsdB, immunomodulator SasH, functionally uncharacterized SasD, biofilm-related SasG and methicillin resistance-related FmtB. However, only Spa and SasH modified their proteomic and mRNA profiles in parallel in the parent and its agr- mutant, whereas all other LPXTG-proteins modified their proteomic profiles independently of their mRNA. Moreover, ClfA became highly transcribed and active in fibrinogen-adherence tests during late growth (24 h), whereas it remained poorly detected by proteomics. On the other hand, iron-regulated IsdA-B-C increased their protein expression by >10-times in iron-poor conditions. Thus, proteomic, transcriptomic, and adherence-phenotype demonstrated differential profiles in S. aureus. Moreover, trypsin peptide signatures suggested differential protein domain exposures in various environments, which might be relevant for anti-adhesin vaccines. A comprehensive understanding of the S. aureus physiology should integrate all three approaches. |
| Databáze: | OpenAIRE |
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