Comparative bait fishing shows different interactions of the two CheW proteins. A Plot of the association score of proteins identified in a comparative bait fishing experiment with both CheW proteins. Proteins bound to a higher extent to CheW2 than to CheW1 appear with a positive association score and proteins bound to higher extent to CheW1 than to CheW2 with a negative association score. Proteins bound to both baits to the same extent as well as background proteins appear with an association score close to 0. B Representative extracted ion chromatograms of a peptide of CheA (N-terminal peptide MDDYLEAFVR). The upper panel shows the 13C form (fished by CheW2) and the lower panel the 12C form (fished by CheW1).