zDB: bacterial comparative genomics made easy

The analysis and comparison of genomes relies on different tools for tasks such as annotation, orthology prediction and phylogenetic inference. Most tools are specialized for a single task and additional efforts are necessary to integrate and visualize the results. To fill this gap, we developed zDB, an application that integrates an analysis pipeline and a visualization platform. Starting from annotated Genbank files, zDB identifies orthologs and infers a phylogeny for each orthogroup. A species phylogeny is also constructed from shared single-copy orthologs. The results can be enriched with Pfam protein domain prediction, COG and KEGG annotations and Swissprot homologs. The web application allows searching for specific genes or annotations, running Blast queries and comparing genomic regions and whole genomes. The metabolic capacities of organisms can be compared at either the module or pathway levels. Finally, users can run queries to examine the conservation of specific genes or annotations across a chosen subset of genomes and display the results as a list of genes, Venn diagram or heatmaps. Those features will make zDB useful for both bioinformaticians and researchers more accustomed to laboratory research. zDB is perfectly suited to process datasets with tens to hundred of genomes on a desktop machine.