Pintacuda Guido, Hohenthanner Karin, Otting Gottfried, Müller Norbert
Department of Medical Biochemistry and Biophysics, Karolinska Institute, S-171 77 Stockholm, Sweden.
J Biomol NMR. 2003 Oct;27(2):115-32. doi: 10.1023/a:1024926126239.
The (15)N-HSQC spectra of low-spin cyano-met-myoglobin and high-spin fluoro-met-myoglobin were assigned and dipole-dipole-Curie-spin cross-correlated relaxation rates measured. These cross-correlation rates originating from the dipolar (1)H-(15)N interaction and the dipolar interaction between the (1)H and the Curie spin of the paramagnetic center contain long-range angular information about the orientation of the (1)H-(15)N bond with respect to the iron-(1)H vector, with information measurable up to 11 A from the metal for the low-spin complex, and between 10 to 25 A for the high-spin complex. Comparison of the experimental data with predictions from crystal structure data showed that the anisotropy of the magnetic susceptibility tensor in low spin cyano-met-myoglobin significantly influences the cross-correlated dipole-dipole-Curie-spin relaxation rates.
测定了低自旋氰化高铁肌红蛋白和高自旋氟代高铁肌红蛋白的(15)N-HSQC谱，并测量了偶极-偶极-居里自旋交叉相关弛豫率。这些源于偶极(1)H-(15)N相互作用以及(1)H与顺磁中心居里自旋之间偶极相互作用的交叉相关率，包含了关于(1)H-(15)N键相对于铁-(1)H矢量取向的远程角信息，对于低自旋配合物，从金属起可测量到11 Å的信息，对于高自旋配合物，则在10至25 Å之间。将实验数据与晶体结构数据的预测结果进行比较表明，低自旋氰化高铁肌红蛋白中磁化率张量的各向异性显著影响交叉相关的偶极-偶极-居里自旋弛豫率。
