Table II.

Resolvable Reactions in the Flicker-open and -closed States of Cysteine-mutant Channels with MTS Derivatives

Mutant		Reagent (cis)		Reagent (trans)		No. of reactions analyzed		No. reacted from open state		No. reacted from closed state
V347C				EA		3				1 (?)
				ET		43		2 (?)		1; 2 (?)
G348C				EA		10		8		1; 1 (?)
				ET		14		6		3; 1 (?)
		EA				6		1; 1 (?)		2; 1 (?)
V351C				EA		5				4
				ET		39				7
				ES		21				7
		ET*				14				5; 2 (?)
D352C				EA		Several		1
				ES		Several		6; 1 (?)		2
I353C				EA		6				3; 1 (?)
		EA				4				2
G354C				EA		40				9
		EA				5				1
F355C				EA		29		8; 1(?)		6; (2?)
		EA				5		1; 2 (?)
A356C				EA		15		1		4; 3 (?)
Y358C				EA		7		1		1
N359C				ET		15		2		3
				EA		8		3		5
		EA				4		4

The membrane potential was held at +60 mV. The pH conditions were cis 5.3/trans 7.2, except for the reactions of V351C with cis ET, which were cis pH 7.2/trans pH 7.2. A question mark in parenthesis next to an entry in a “No. reacted from . . .” columns indicates that, in addition to the number of resolvable reactions, this many more reactions probably reacted from the indicated flicker open or closed state also, but it is not entirely clear. Note that only a small fraction of the number of reactions analyzed was resolvable. The reactions of some mutants with MTS derivatives were not analyzed at high time resolution to determine whether they reacted from the flicker-closed or -open state. Some mutants that were analyzed, but could not be resolved, are not included in the table. EA = MTS-EA⁺; ET = MTS-ET⁺; and ES = MTS-ES⁻.  

^*pH Conditions cis 7.2/trans 7.2.