Two TIR-like domain containing proteins in a newly emerging zoonotic Staphylococcus aureus strain sequence type 398 are potential virulence factors by impacting on the host innate immune response.

Staphylococcus aureus, sequence type (ST) 398, is an emerging pathogen and the leading cause of livestock-associated methicillin-resistant S. aureus infections in Europe and North America. This strain is characterized by high promiscuity in terms of host-species and also lacks several traditional S.

To con protection: TIR-domain containing proteins (Tcp) and innate immune evasion.

The innate immune system provides the host's first line of defence against invading pathogens. Key to the stimulation of the innate immune response is pattern-recognition receptors (PRRs), such as Toll-like receptors (TLRs), which recognize microbial-associated molecular patterns (MAMPs). Binding of MAMPs to TLRs triggers a signalling cascade resulting in the production of pro-inflammatory mediators.