Fig. 1.

The chemotaxis transduction network in E. coli [1, 5]. Several types of chemoreceptors (in different colors and shapes) specifically sense different kinds of chemoeffectors in the environment, including attractants (red spots or yellow triangles), repellents (blue squares), antagonists (green diamonds or purple ovals) and other environmental effectors (blue arrows). One trimer of receptor dimers, one CheW protein, and one CheA monomer (the other CheA monomer is shown as a dashed line) are shown in the figure. Receptor methylation sites are shown as white (unmethylated) or black (methylated) circles. The phosphoryl groups are shown as yellow stars