Colombos' major features include:
1. Access to gene expression compendia that combine information from different platforms and experiments.
2. Integration of information from main curated microbial databases allowing the user to interactively browse and query the compendia for specific genes, pathways, transcriptional regulation mechanisms, and more.
3. An extensive formal sample annotation and higher level condition contrast ontology, allowing the user to interactively browse and query the compendia not only for specific arrays, samples, or experiments, but also for specific experimental conditions and biological processes.
4. A suite of flexible yet intuitive tools to explore, analyze and visualize the expression data in the compendia, including the ability to integrate data across different species based on defined clusters of homologuous genes.
5. Programmatic access to the database via a REST web service. We also provide an API to connect to and query the COLOMBOS database directly from within R (Rcolombos).