Use of genomics and proteomics to develop better diagnostic tools for use in infectious diseases

The genome is a rather constant entity while the proteome is constantly changing through its biochemical interactions with the genome. One organism will have radically different protein expression in different parts of its body and at different stages of its life cycle. The goal in the post-genome era is to determine how the proteome is organized into functional, higher-order networks, by mapping all constitutive and dynamic protein-protein interactions. The availability of complete genome sequences has dramatically changed the opportunities for developing novel and improved diagnosis of infectious diseases. Proteome databases have been developed for Escherichia coli, Bacillus subtilis, Haemophilus influenzae and Pseudomonas aeruginosa. Study of genomics and proteomics of microbial infections, named infectomics, represents the scientific challenge of the future. The study of infectomics is very exciting, with the limitation that determination of bacterial proteomes should be performed when they are growing in association with their host and its immune system. In conclusion, expectations from proteomics mainly concern development of a 'final solution' allowing for direct diagnosis of infectious diseases by analysis of a specimen's proteins.