Figure 2

X-band EPR spectrum of oxidized HLMW b ₅ measured at 15K and effects of the mutations on the spectrum. Following samples in oxidized form in 50 mM sodium phosphate buffer pH 7.0 were frozen at 77K and their respective EPR spectrum was measured at 15K. HLMWb₅ (trace a, 0.50 mM); A59V (trace b, 0.12 mM); A59 S (trace c, 0.19 mM); G67A (trace d, 0.20 mM); G67 S (trace e, 0.24 mM), and L51I (trace f, 0.27 mM). Ordinate of each spectrum was normalized appropriately based on the concentration for an easier visualization. Other conditions are described in the text. The signal around g = 2 in G67A mutant (d) was due to a contaminant from EPR tube.