Proton magnetic resonance studies on short duplexes. I. Helix formation by the duplex set GpApGpC:GpCpUpC

1978 ◽  
Vol 56 (17) ◽  
pp. 2243-2248 ◽  
Author(s):  
Donald W. Hughes ◽  
Russell A. Bell ◽  
Thomas E. England ◽  
Thomas Neilson
Keyword(s):  
Magnetic Resonance ◽  
Chemical Shift ◽  
Proton Magnetic Resonance ◽  
Neck Region ◽  
Trna Synthetase ◽  
Optical Methods ◽  
Aminoacyl Trna Synthetase ◽  
Double Stranded Rna ◽  
Magnetic Resonance Studies ◽  
Helix Formation

Proton magnetic resonance bas been used to investigate the double stranded RNA helix GAGC:GCUC, whose sequence corresponds to the duplex neck region of several tRNAs, a possible aminoacyl-tRNA synthetase recognition site. The nonexchangeable base and ribose anomeric resonances of the separate tetranucleotides were characterized by linear and predominantly upfield chemical shift changes as the temperature was decreased from 65 to 15 °C. When these strands were mixed nonlinear, sigmoidal shift changes consistent with base pairing were observed. The melting temperature of the duplex was determined to be 42 ± 1 °C which was in excellent agreement with the value obtained from optical methods. This is the first 1Hmr study of a non-self-complementary duplex prepared from synthetic tetraribonucleotides.

Proton Magnetic Resonance Studies of 2′-Deoxythymidine, its 3′- and 5′-Monophosphates and 2′-Deoxythymidylyl-(3′, 5′)-2′ -deoxythymidine in Aqueous Solution

1974 ◽  
Vol 52 (19) ◽  
pp. 3353-3366 ◽  
Author(s):  
Donald J. Wood ◽  
Frank E. Hruska ◽  
Kelvin K. Ogilvie
Keyword(s):  
Aqueous Solution ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Proton Magnetic Resonance ◽  
Coupling Constant ◽  
Experimental Conditions ◽  
Magnetic Resonance Studies ◽  
Spectral Bands ◽  
Conformational Properties

Proton magnetic resonance studies of 2′-deoxythymidine, its 3′ and 5′-monophosphates and the dideoxynucleoside monophosphate, 2′-deoxythymidylyl-(3′,5′)-2′-deoxythymidine are described. Assignment of the spectral bands are carried out and the derived chemical shift and coupling constant data are discussed in terms of the conformational properties of these molecules. The main conclusion reached is that 3′- and 5′-phosphorylation as well as incorporation into the dinucleoside monophosphate at either the 3′- or 5′-terminus has only slight effects on the conformation of thymidine under the experimental conditions employed.

Proton magnetic resonance studies on short duplexes. II. The self-complementary oligoribonucleotide CpApUpG

1978 ◽  
Vol 56 (17) ◽  
pp. 2249-2252 ◽  
Author(s):  
Paul J. Romaniuk ◽  
Thomas Neilson ◽  
Donald W. Hughes ◽  
Russell A. Bell
Keyword(s):  
Magnetic Resonance ◽  
Chemical Shift ◽  
Proton Magnetic Resonance ◽  
Double Helix ◽  
The Self ◽  
Proton Nuclear Magnetic Resonance ◽  
Base Pairs ◽  
Temperature Range ◽  
Helix Formation ◽  
Nmr Study

Proton nuclear magnetic resonance was used to examine double helix formation in the self-complementary oligoribonucleotide CAUG in neutral D2O containing 1.0 M NaCl. Using the procedure of incremental assignment all the nonexchangeable base and ribose anomeric protons could be assigned and were observed over the temperature range of 70 to 4 °C. The chemical shift changes that occurred over this temperature range were sigmoidal in nature which is indicative of base-pairing. From the plot of chemical shift vs. temperature a Tm of 24 ± 1 °C was determined. This is the first nmr study of a duplex formed from tetranucleotides which contains two internal A•U base pairs.

NUCLEAR MAGNETIC RESONANCE STUDIES: IX. THE CHEMICAL SHIFT OF THE FORMYL PROTON IN ALIPHATIC ALDEHYDES

1966 ◽  
Vol 44 (1) ◽  
pp. 45-51 ◽  
Author(s):  
R. E. Klinck ◽  
J. B. Stothers
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Aliphatic Aldehydes ◽  
Magnetic Resonance Studies ◽  
Unsaturated Aldehydes ◽  
Potential Use ◽  
Nuclear Magnetic

The effects of structure on the shielding of formyl protons of aliphatic aldehydes have been examined. The survey included examples of acyclic, alicyclic, and α, β-unsaturated aldehydes. The potential use of these results as an aid for structural elucidations is discussed, and the limitations are noted.

A STUDY OF TAUTOMERISM IN CYCLIC β-DIKETONES BY PROTON MAGNETIC RESONANCE

1965 ◽  
Vol 43 (11) ◽  
pp. 3057-3062 ◽  
Author(s):  
Natsuko Cyr ◽  
Leonard W. Reeves
Keyword(s):  
Magnetic Resonance ◽  
Chemical Shift ◽  
Proton Magnetic Resonance ◽  
Enthalpy Change ◽  
Enol Form ◽  
Proton Resonance ◽  
Kcal Mole ◽  
Intensity Measurements ◽  
Acetonitrile Solutions ◽  
Monomer Form

The keto–enol equilibrium of cyclohexane-1,3-dione in chloroform is best interpreted from proton resonance measurements as[Formula: see text]K1 and K2 may be separately determined from chemical shift measurements of the enol-OH proton and intensity measurements of peaks assigned to keto and enol forms. K1 and K2 are satisfactorily independent of concentrations except in very dilute solutions where intensity measurements become unreliable. The overall equilibrium constant K = K1 × K22 can be obtained for the same molecule in acetonitrile solutions where the enol monomer form is in very low concentration. 5,5′-Dimethylcyclohexane-1,3-dione in chloroform has less enol form than the unsubstituted molecule. The enthalpy change associated with 'K' for cyclohexane-1,3-dione in chloroform is 2.05 ± 0.5 kcal mole−1.

Sign in / Sign up

Export Citation Format

Share Document