Advances in environmental genomics: towards an integrated view of micro-organisms and ecosystems.

Microbial genome sequencing has, for the first time, made accessible all the components needed for both the elaboration and the functioning of a cell. Associated with other global methods such as protein and mRNA profiling, genomics has considerably extended our knowledge of physiological processes and their diversity not only in human, animal and plant pathogens but also in environmental isolates. At a higher level of complexity, the so-called meta approaches have recently shown great promise in investigating microbial communities, including uncultured micro-organisms. Combined with classical methods of physico-chemistry and microbiology, these endeavours should provide us with an integrated view of how micro-organisms adapt to particular ecological niches and participate in the dynamics of ecosystems.