The chemical-in-μwell: a high-throughput technique for identifying solutes eliciting a chemotactic response in motile bacteria

Bacteria, and in particular marine bacteria, can be found in environments that are poor in nutrients. To survive, they are able to move toward more favorable niches by a mechanism called chemotaxis, whose first step consists in the detection of substrates by chemoreceptors. We developed a chemotactic assay enabling rapid testing of several hundred different solutes and we identified several molecules eliciting a chemotactic response from two aquatic Shewanella species. We propose that this assay be used for other bacteria to determine the repertoire of chemotactic molecules, generally not clearly elucidated.