Figure 8.
1H-15N HSQC spectrum of folded P protein in various concentrations of K3[Cr(CN)6]. The protein concentration was 200 μM with 20 mM sulfate in 20 mM cacodylate buffer pH 6.5. The [Cr(CN)6]3− concentration ranged from 2.5 μM to 50 μM. The spectra with [Cr(CN)6]3− concentrations higher than 50 μM are not shown in the plot. Higher concentrations of [Cr(CN)6]3− broaden the resonances of many residues, which may result from nonspecific binding of [Cr(CN)6]3− thereby masking the effects due binding at the two high affinity sites.