FIG. 2.

Absorption spectra of cell extracts of the wild-type strain, strains lacking thioredoxin 2 (trxC), glutaredoxin 3 (grxC), or glutathione synthetase B (gshB), and grxC- and gshB- complemented strains. Cultures were grown semiaerobically in malate medium supplemented with appropriate antibiotics overnight. Samples were prepared as described in Materials and Methods. Cell extracts were scanned from 500 to 900 nm with a Perkin-Elmer Lambda 12 spectrophotometer. Strains are listed in Table 1.