Phosphorylation kinetics of CheY mutants by PAM. Reactions with
CheY87TA (○,●), CheY106YA
(□,■), and CheY109KR (⋄,♦) were performed in
the absence (open symbols) and the presence (closed symbols) of 1 mM
FliM peptide. Observed first-order rate constants
(kobs) were determined from individual
phosphorylation time courses at the indicated phosphodonor
concentrations. Constant ionic strength was maintained.