We are conducting a comparative study of the copper homeostasis system in several Leptospira species representing the three main evolutionary clades: pathogenic, intermediate, and saprophytic. Copper is both an essential trace element and a toxic agent at high concentrations, particularly through its pro-oxidant effects. Pathogenic bacteria are frequently exposed to copper during infection, as copper is used by host immune cells as part of their antimicrobial arsenal.
Preliminary genomic analyses suggest differences in copper detoxification systems among Leptospira species, which may reflect adaptation to different ecological niches or levels of pathogenicity. However, genome mining approaches alone may not reveal all genes involved, especially those that are poorly annotated or not previously associated with copper homeostasis.
To complement these analyses and gain a more comprehensive view of the copper stress response, we plan to perform RNA-Seq on selected Leptospira strains exposed to copper stress. The aim is to identify differentially expressed genes in response to copper, including both known detoxification genes and potentially novel candidates. This transcriptomic data will help us refine our understanding of the molecular mechanisms involved, and may support further evolutionary and functional studies.
Samples will include biological replicates of strains from the different clades, treated or not with copper, to allow for comparative transcriptomic analyses.
