Exploring genomic diversity in Clostridium botulinum using DNA microarrays

Rapid increases in the number of available Clostridium botulinum genome sequences have permitted the development of new molecular subtyping methods for this organism. Our laboratory has developed various DNA microarrays in an effort to differentiate strains based on differences in gene content. This review will focus on both high density comparative genomic hybridisation (CGH) microarrays and various focused (low density) oligonucleotide spotted microarrays. Comparison of gene content using DNA microarrays provides investigators with the ability to simultaneously differentiate unrelated strains and to identify strain variable genes. Such genes may play important roles in the pathogenesis, growth, and survival of this organism. Moreover, probes may be optimised as new genome sequences become available leading to improvements in the ability to characterise novel or unusual strains.