TABLE 1.

DTNB analysis of free thiols in OhrR and mutant proteins under denaturing conditions

OhrR (remaining cysteine[s])No. of free thiols per subunit
ReducedaPeroxide treatedb
OhrR (C22, C127, C131)2.79 ± 0.220.82 ± 0.14
C22S (C127, C131)1.89 ± 0.111.78 ± 0.16
C127131S (C22)1.07 ± 0.040.010 ± 0.001
  • a Proteins were prepared under reducing conditions.

  • b Proteins were exposed to 1 equivalent of cumene hydroperoxide.