Genomic analysis of the host-specific pathogenesis of Staphylococcus aureus

Staphylococus aureus causes life-threatening infections of humans and economically important infections of domestic animals such as mastitis. There is very limited cross-species transfer of infections suggesting that individual S. aureus clones have evolved the mechanisms required to infect a single host only. The purpose of this project is to identify what factors are produced by S. aureus which contribute to pathogenesis of specific animal hosts. In addition, the evolution of S. aureus clones infecting different animal species will be explored. The work will be carried out using whole-genome microarrays. Microarrays consist of glass slides which can represent each of the genes identified in the whole genome of that organism. The microarray allows the comparison of the genome content of many bacterial isolates. We will then determine if the genes are being expressed during animal infection by measuring the antibody response to specific factors. This would indicate that the proteins are involved in host-pathogen interactions and may play a role in causing disease. Taken together, this study will provide new insights into S. aureus evolution and pathogenesis and will identify new targets for vaccine or therapeutic development.

Staphylococcus aureus is a major human and animal pathogen. Population genetic analyses have shown that there is limited cross-species transfer of S. aureus strains suggesting that they have evolved to infect a preferred host. The current project involves the use of genomic approaches to investigate the evolution of host-specialisation in S. aureus natural populations and to explore its molecular basis.