HyperCAT: an extension of the SuperCAT database for global multi-scheme and multi-datatype phylogenetic analysis of the Bacillus cereus group population

The Bacillus cereus group of bacteria includes species that are of significant medical and economic importance. We previously developed the SuperCAT database, which integrates data from all five multilocus sequence typing (MLST) schemes available to infer the genetic relatedness within this group. Since large numbers of isolates have been typed by other techniques, these should be incorporated in order to provide the most comprehensive and truly global view of the B. cereus group population. The SuperCAT system has been extended into a new database, HyperCAT, with two main additions. First, an extended supertree approach was applied to combine the phylogenetic information available from MLST, amplified fragment length polymorphism and multilocus enzyme electrophoresis. Secondly, a tree-independent clustering algorithm was designed to build superclusters of genetically closely related isolates sharing identical genotyping data. The superclusters were then mapped onto the supertree to generate an integrative genetic and phylogenetic snapshot of the B. cereus group population currently incorporating 2143 isolates. HyperCAT is freely accessible at the University of Oslo's typing website, which has also been upgraded with TNT software, allowing improved and ultra-fast supertree reconstructions. In addition, novel and advanced tools have been included for interactive viewing and navigation of trees, clusters and networks. Database URL: http://mlstoslo.uio.no/