首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Relaxation-optimized NMR spectroscopy of methylene groups in proteins and nucleic acids
Authors:Miclet Emeric  Williams Jr David C  Clore G Marius  Bryce David L  Boisbouvier Jérôme  Bax Ad
Institution:Contribution from the Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0520, USA.
Abstract:A large fraction of hydrogens in proteins and nucleic acids is of the methylene type. Their detailed study, however, in terms of structure and dynamics by NMR spectroscopy is hampered by their fast relaxation properties, which give rise to low sensitivity and resolution. It is demonstrated that six different relaxation interference processes, involving 1H-13C and 1H-1H dipolar interactions and 1H and 13C chemical shift anisotropy, can be used simultaneously to mitigate these problems effectively. The approach is applicable to the majority of NMR experiments commonly used to study side chain and backbone conformation. For proteins, its efficiency is evaluated quantitatively for two samples: the third IgG-binding domain from Streptococcal Protein G and the protein calmodulin complexed with a 26-residue target peptide. Gains in both resolution and sensitivity by up to factors of 3.2 and 2.0, respectively, are observed for Gly residues at high magnetic field strengths, but even at much lower fields gains remain substantial. The resolution enhancement obtained for methylene groups makes possible a detailed analysis of spectral regions commonly considered inaccessible due to spectral crowding. For DNA, the high resolution now obtainable for C5' sites permits an H5'/H5'-based sequential NOE assignment procedure, complementary to the conventional base-H1'/H2'/H2' pathway.
Keywords:
本文献已被 PubMed 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号