Table 1.

Autodephosphorylation rate constants of CheY, model response regulators, and CheY mutants.

Amino acid at positiona			Wild type CheY & model response regulators		CheY mutants
'14'	'59'	'89'	Nameb	kdephosph (min−1)c	Name	kdephosph (min−1)c
F	N	E	E. coli CheY	2.5 ± 0.322
E	M	R	E. coli PhoB	0.00944	CheYPhoB	0.11 ± 0.0022
E	M	L	E. coli CusR	NAd	CheYCusR	0.060 ± 0.006
E	R	H	S. mel. FixJ	0.00545	CheYFixJ DctD	0.060 ± 0.008
D	R	H	S. mel. DctD	0.00746
Q	K	Y	B. sub. Spo0F	0.00447	CheYSpo0F	0.085 ± .00922
E	N	R	E. coli ArcA	0.00548/0.0249	CheYArcA	0.40 ± 0.10

^aAll response regulators on the same line of the table have the indicated combination of variable active site amino acids.

^bSpecies abbreviations: E. coli, Escherichia coli; S. mel., Sinorhizobium meliloti; B. sub., Bacillus subtilus.

^cSuperscript indicates literature source of previously published data. Values measured in our laboratory include the mean ± standard deviation for at least two independent measurements. Measurements from other laboratories are rounded to one significant figure.

^dNot available. We are unaware of any k_dephos measurement for CusR.