Biomedical Engineering Reference
In-Depth Information
CHAPTER 2
Low-c Nuclei Detection
Experiments for Biomolecular
NMR
KOH TAKEUCHI
a,b
, MAAYAN GAL
a
, ICHIO SHIMADA
b,c
AND GERHARD WAGNER*
a
a
Department of Biochemistry and Molecular Pharmacology, Harvard Medical
School, Boston, MA 02115, USA;
b
Biomedicinal Information Research
Center, National Institute of Advanced Industrial Science and Technology,
Tokyo 135-0064, Japan;
c
Department of Physical Chemistry, Graduate School
of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
*E-mail: gerhard_wagner@hms.harvard.edu
2.1 Introduction
Solution NMR is an established technique for studying the structure and
dynamics of well-behaved macromolecules. However, its use has severe
limitations when studying fast-relaxing systems, such as large, unstructured,
and/or paramagnetic proteins. These limitations originate from signal losses
due to fast transverse relaxation, which leads to an attenuated sensitivity and
reduced spectral resolution. These affect pulse sequences not only during
evolution or detection periods but also during mixing and coherence transfers.
Thus, careful selection of transfer pathways, and the decision of which nuclei
to detect or not to detect is of prime importance for optimal extraction of
structural information from such challenging systems.
