Heteronuclear filters in two-dimensional [¹H, ¹H]-NMR spectroscopy: combined use with isotope labelling for studies of macromolecular conformation and intermolecular interactions

Abstract

The use of heteronuclear filters enables the editing of complex 1H nuclear magnetic resonance (NMR) spectra into simplified subspectra containing a lesser number of resonance lines, which are then more easily amenable to detailed spectral analysis. This editing is based on the creation of heteronuclear two-spin or multiple-spin coherence and discrimination between protons that do or do not participate in these heteronuclear coherences. In principle, heteronuclear editing can be used in conjunction with one-dimensional or multidimensional 1H-NMR experiments for studies of a wide variety of low-molecular-weight compounds or macromolecular systems, and is implicitely applied in a wide range of heteronuclear NMR experiments with proton detection (e.g. Bax et al. 1983; Griffey & Redfield, 1987). In the present article we shall focus on the use of heteronuclear filters in two-dimensional (2D) [1H, 1H]-NMR experiments. The selection of the material covered was primarily motivated by its impact on the practice of protein structure determination in solution, and on NMR studies of intermolecular interactions with biological macromolecules. Section 2 surveys potential applications of heteronuclear filters in this area. The remainder of the article is devoted to an introduction of the theoretical principles used in heteronuclear filters, and to a detailed description of the experimental implementation of these measurements. In writing the review we tried to minimize redundancy with the recent article in Quarterly Review of Biophysics by Griffey & Redfield (1987) and to concentrate on experiments that were introduced during the period 1986–9.

Solution Structure of the Severe Acute Respiratory Syndrome-Coronavirus Heptad Repeat 2 Domain in the Prefusion State

“…Structure Determination-The calculation of a symmetric trimer using NMR is a challenging task and requires the use of isotopic-filtered NOE experiments (reviewed in Ref. 61). In the present work, intermolecular NOEs were identified by a three-dimensional F1-filtered F2-edited 1 H-13 C NOESY-HSQC (48) experiment recorded on a 1:1 mixture of 13 C/ 15 N: 12 C/ 14 N-labeled S2-HR2.…”

Structural Basis for Homodimerization of the Src-associated during Mitosis, 68-kDa Protein (Sam68) Qua1 Domain

“…For backbone and side chain assignment CBCA(CO)NH, CBCANH and (H)CCH-TOCSY spectra were recorded (31). Distance information was obtained from 15 N-and 13 C-edited NOESY spectra with a mixing time of 70 ms. To distinguish interand intramolecular NOEs, a set of isotope-edited and filtered NOESY spectra was recorded (31,32). Experiments were carried out using a 1 mM uniformly 15 N/ 13 C-labeled or 2 mM asymmetrically 15 N/ 13 Clabeled Qua1(95-156) sample, respectively.…”

“…In the case of a symmetric homodimer, the NOESY spectrum contains both intramolecular and intermolecular cross-peaks. To unambiguously distinguish intermolecular from intramolecular NOEs, isotope-filtered experiments were recorded on an asymmetrically 15 N/ 13 C-labeled sample (31,32). To obtain such a sample, equimolar amounts of uniformly 15 N/ 13 C-labeled and unlabeled Qua1 are mixed.…”

NMR Studies of the Escherichia coli Trp Repressor ·trpRs Operator Complex

“…As shown above, the NOEs from the thymidine methyl groups were particularly useful, and could not be used from the protonated complex, as there was overlap with the many methyl groups in the protein. While similar information could be obtained from '"C-labelled protein, using either 13C filter experiments (reviewed in [27)) or purge pulses [28] to observe only the protons attached to '*C, the filtering makes the experiment less sensitive than using deuteration. An additional advantage of this approach is that the deuterated complex relaxes more slowly than the protonated (and "C-labelled) one giving much sharper lines and reducing spin diffusion effects.…”