FIGURE 8.

NMR relaxation parameters and membrane topology of MMP23-PD in DPC micelles at 30 °C and 600 MHz. A–D, ¹H-¹⁵N steady-state NOE values (A), longitudinal (R₁) (B), transverse (R₂) ¹⁵N relaxation rates (C), and ratio of R₁ to R₂ for MMP23-PD (D). E, ratio of peak intensities before and after the addition of the water-soluble paramagnetic spin label Gd(DTPA-BMA) (19). F, peak intensities for the Clean SEA-HSQC spectrum (Cleanex) (18) of MMP23-PD in DPC micelles, measuring the exchange of backbone amide protons with solvent. Sites for which no values were determined are denoted by a P for proline residues or an asterisk for unassigned residues. Secondary structure elements derived from CSI values are illustrated at the top and boxed by a dotted line in each figure.