Table IV

Waiting Times for Reactions of Cysteine-substituted Residues 329–336 with MTS-EA+

MutantpH Conditions (cis/trans)EA concentration cisEA concentration transNo. reactions observedWaiting time for reaction
μMμMs
V329C5.2/7.2EA (233)0*
5.2/7.2EA (465)0*
7.2/7.2EA (460)210–25
7.2/7.2EA (380)EA (920)1<3
7.2/7.2EA (300–380)3–4<3
A330C5.2/7.2EA (600–680)2–3>30
7.2/7.2EA (460–760)75–40
Q331C5.2/7.2EA (678)1140
7.2/7.2EA (508)312, 30, 60
S332C5.2/7.2EA (400–810)0*
7.2/7.2EA (810)215, 17
7.2/7.2EA (135)2<5
I333C5.2/7.2EA (373–466)EA (373–746)0*
A334C5.2/7.2EA (508)125
7.2/7.2EA (170)3<4
L335C7.2/7.2EA (339)21 and 90
7.2/7.2EA (424)EA (847)31–10
S336C5.2/7.2EA (504)EA (864)0*
7.2/7.2EA (216–504)5–65–25
7.2/7.2EA (504)EA (864)1∼30
  • The membrane potential was held at +60 mV. In rows where EA is listed under both the cis and trans column, it means EA was added to both sides of the same membrane. EA = MTS-EA+.  

  • * Observed several channels for many minutes without getting any reaction.