2000
Transverse relaxation optimized triple-resonance NMR experiments for nucleic acids
FIALA, Radovan, Jiří CZERNEK a Vladimír SKLENÁŘZákladní údaje
Originální název
Transverse relaxation optimized triple-resonance NMR experiments for nucleic acids
Autoři
FIALA, Radovan, Jiří CZERNEK a Vladimír SKLENÁŘ
Vydání
Journal of Biomolecular NMR, Nizozemí, Kluwer/Escom, 2000, 0925-2738
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10403 Physical chemistry
Stát vydavatele
Nizozemské království
Utajení
není předmětem státního či obchodního tajemství
Impakt faktor
Impact factor: 3.592
Kód RIV
RIV/00216224:14310/00:00000058
Organizační jednotka
Přírodovědecká fakulta
UT WoS
000086622900002
Klíčová slova anglicky
C-13 CSA; C-13 relaxation; HCN experiments; RNA; TROSY
Štítky
Změněno: 8. 10. 2002 15:22, prof. RNDr. Vladimír Sklenář, DrSc.
Anotace
V originále
Triple resonance HCN and HCNCH experiments are reliable methods of establishing sugar-to-base connectivity in the NMR spectra of isotopicaly labeled oligonucleotides. However, with larger molecules the sensitivity of the experiments is drastically reduced due to relaxation processes. Since the polarization transfer between 13C and 15N nuclei relies on rather small heteronuclear coupling constants (11-12 Hz), the long evolution periods (up to 30-40 ms) in the pulse sequences cannot be avoided. Therefore any effort to enhance sensitivity has to concentrate on manipulating the spin system in such a way that the spin-spin relaxation rates would be minimized. In the present paper we analyze the efficiency of the two known approaches of relaxation rate control, namely the use of multiple-quantum coherence - MQ (Griffey and Redfield, 1987; Bax et al., 1989; Grzesiek and Bax, 1995) and of the relaxation interference between chemical shift anisotropy and dipolar relaxation - TROSY (Pervushin et al. 1997; Pervushin et al. 1998a; Pervushin et al. 1998b; Andresson et al. 1998; Rance et al. 1999; Brutcher et al. 1998; Salzman et al. 1998; Salzman et al. 1999). Both theoretical calculations and experimental results suggest that for the sugar moiety (H1'-C1'-N1/9) the MQ approach is clearly preferable. For the base moiety (H6/8-C6/8-N1/9) however, the TROSY shows results superior to the MQ suppression of the dipole-dipole relaxation at moderate magnetic fields (500 MHz) and the sensitivity improvement becomes dramatically more pronounced at very high fields (800 MHz). The pulse schemes of the triple-resonance HCN experiments with sensitivity optimized performance for unambiguous assignments of intra-residual sugar-to-base connectivities combining both approaches are presented.
Návaznosti
GA203/99/0311, projekt VaV |
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