Table 3.

Summary of hypothesized mechanisms of autodephosphorylation rate modulation based on structural comparisons between CheY mutants and wild type CheY or model response regulators

Compared to	CheY Mutant
	CheYPhoB	CheYCusR	CheYFixJ DctD	CheYSpo0F	CheYArcA
Wild type	Obstructiona	Obstruction	Obstruction	Conformation	Conformation
CheY	(Conformation)b	(Conformation)	(Conformation)
Model response regulator	Conformation	NAc	Obstructiond	Unknown	Unknown

^a“Obstruction” means steric obstruction of attacking water molecule in hydrolysis reaction (hypothesis 2 in the text). “Conformation” means interference with the change from active to inactive conformation coupled to autodephosphorylation (hypothesis 3 in the text).

^bSecondary explanation in parentheses

^cNot applicable. No structure of CusR is available for comparison.

^dCheY_{FixJ DctD} was compared to both DctD and FixJ but the latter comparison was not shown in a figure.