Project description:Functionality of the accessory gene regulator (agr) quorum sensing system is an important switch promoting either acute or chronic infections, mediated by the notorious opportunistic human and veterinary pathogen Staphylococcus aureus. Spontaneous alterations of the agr system are known to frequently occur in human healthcare-associated S. aureus lineages. However, data on agr integrity and function are sparse regarding other major lineages. Here we report on the agr system functionality and activity level in mecC-carrying methicillin resistant S. aureus (MRSA) of various animal origins (n=33) in Europe together with closely related isolates of human patients (n=12). Whole genome analysis assigned all isolates to four clonal complexes (CC) with distinct agr types (CC599 agr I, CC49 agr II, CC130 agr III and CC1943 agr IV). Different levels of agr functionality were detected by use of different phenotype assays and proteomics for isolates of each CC, including completely non-functional variants. Genomic comparison of the agr I-IV encoding regions revealed that variants of AgrA and AgrC were associated with these phenotype changes, especially among the isolates of pet- and wild animal origin. Since a role in adaptation is most likely when genomic changes occur independently in divergent lineages, agr variation might foster viability and niche adjustment capacities of rare MRSA lineages.
Project description:Investigation of baseline transcription activity of two different clinical isolates of Staphylococcus aureus with two different susceptibility levels to the antibiotics Vancomycin and Daptomycin.
Project description:High-coverage whole genome sequencing of 11 Brazilian isolates of the root-knot nematode Meloidogyne incognita, presenting different host plant preferences and different geographical origins. Four M. incognita host races had been proposed in the past, based on host (in)compatibility on four different plant strains. The objective was to assess whether genomic variations (SNP) correlate with host range compatibility, geographical origin and host plant of origin.
Project description:Hybridisation of reference strains to the VirEp Staphylococcus aureus microarray, and characterisation of different S. aureus isolates from different locations and associated with different diseases.
Project description:Investigation of baseline transcription activity of two different clinical isolates of Staphylococcus aureus with two different susceptibility levels to the antibiotics Vancomycin and Daptomycin. Two different strains of Staphylococcus aureus, one that is fully Vancomycin and Daptomycin Sensitive and one with decreased Vancomycin and Daptomycin Sensitivity - grown to mid-log phase in rich broth.