TABLE 1.

Pseudorevertants of the H230A mutant

Selection temp (°C)Second-site mutationaChange in nucleotide sequencebNo. of independent isolates
28G83DGGC → GAC1
L44FTTG → TTT2
V178AGTC → GCC5
S120PTCT → CCT1
Q187LCAG → CTG2
T70AACT → GCT
F200LTTC → TTG1
37Q187LCAG → CTG
S120YTCT → TAT1
M228IATG → ATA
T234RACA → AGA1
  • a Shown are second-site mutations present in addition to the H230A mutation in the pseudorevertants. L44F is the same amino acid change found in the srf-4 mutant, and V178A is the same amino acid change found in the srf-5 mutant.

  • b Nucleotide changes found in the pseudorevertants are highlighted in bold.