Figure 2.

Effect of adaptation site modification on maximum CheA kinase activity. For each reconstituted receptor–kinase complex possessing adaptation sites that were modified by amidation as indicated, the CheA kinase activity was measured in the receptor-coupled kinase assay and normalized to that for the wild-type complex measured in parallel. Filled bars indicate the activity in the presence of 5 mM α-methyl d,l-aspartate, and open bars indicate the kinase activity in the absence of attractant. Also shown is the CheA kinase activity observed for membranes lacking aspartate receptor. Experimental conditions were as described in the Figure 1 legend.