The Multinuclear NMR Approach to Peptides

Deslauriers, Roxanne; Smith, Ian C. P.

doi:10.1007/978-1-4615-6537-6_5

Cited by 60 publications

(7 citation statements)

References 274 publications

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“…11 In the first place, the changes in shift with temperature are in the direction expected for increasing hydrogen 12 and do not differ greatly from the -6 to -10 ppb/K for the temperature coefficients of amide proton resonances in extended-chain peptide and protein structures and the smaller temperature coeefficients of about -4 ppb/K for amides not accessible to solvent or hydrogen bonded in tighter protein environments. 13 Second, although, as mentioned earlier, the slopes of the shift changes with temperature do not differ much, the intercepts do change substantially with concentration. Third, as Figures 2-4 show, the cis and trans protons do not have the same slopes, which is consistent with differential hydrogen bonding involving these different types of protons.…”

Section: Self-associationmentioning

confidence: 52%

An NMR Investigation of the Effect of Hydrogen Bonding on the Rates of Rotation about the C−N Bonds in Urea and Thiourea

1996

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Abstract:The interaction between urea and tetrabutylammonium acetate was investigated in dimethylformamide/ dimethyl sulfoxide solutions using 1 H and 15 N NMR. The chemical-shift behavior of the urea protons is consistent with a urea-acetate hydrogen-bonded complex involving both carboxylate oxygens and the urea hydrogens trans to the carbonyl oxygen with K assoc ) 120 ( 10. Line shape analysis of the temperature-dependent 1 H NMR spectra show that ∆G q for rotation about the C-N bond of urea changes only slightly from 11.0 ( 0.1 to 11.2 ( 0.1 kcal/mol on 1:1 molar addition of tetrabutylammonium acetate to a dilute solution of urea. A parallel investigation of the interaction of thiourea with tetrabutylammonium acetate gave a binding constant, K assoc ) 90 ( 10. The ∆G q for rotation about the C-N bond of thiourea was found to increase from 13.5 ( 0.1 to 14.0 ( 0.1 kcal/mol on 1:1 addition of tetrabutylammonium acetate to a dilute solution of thiourea in dimethylformamide/dimethyl sulfoxide. Measurements were also made of the self-association of several ureas and of ∆G q for rotation about both C(O)-N bonds of 1,1-dimethylurea.

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Section: Self-associationmentioning

confidence: 52%

An NMR Investigation of the Effect of Hydrogen Bonding on the Rates of Rotation about the C−N Bonds in Urea and Thiourea

1996

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“…NOESY (13) spectra (mixing time of 200-500 ms), TOCSY (14) spectra (mixing time of 70 ms) and DQF-COSY (15) spectra were acquired at 298 K and used for the assignment of the 1H-NMR resonances. Suppression of the H2O resonance for the NOESY, TOCSY and DQF-COSY spectra was achieved using pulse field gradients (16,17). Temperature coefficients (16) and hence the patterns of backbone hydrogen bonding were assessed by monitoring the chemical shift values of the amide backbone protons with changes in temperature (277, 285, 298 K) in the DQF-COSY and TOCSY experiments.…”

Section: Nmrmentioning

confidence: 99%

“…Suppression of the H2O resonance for the NOESY, TOCSY and DQF-COSY spectra was achieved using pulse field gradients (16,17). Temperature coefficients (16) and hence the patterns of backbone hydrogen bonding were assessed by monitoring the chemical shift values of the amide backbone protons with changes in temperature (277, 285, 298 K) in the DQF-COSY and TOCSY experiments. 2D data were processed on an O2 Silicon graphics work station using Felix 98 software.…”

Section: Nmrmentioning

confidence: 99%

Activating the ryanodine receptor with dihydropyridine receptor II-III loop segments: size and charge do matter

Green¹,

Pace²,

Young³

et al. 2004

Front Biosci

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Excitation-contraction coupling in skeletal muscle is thought to depend on a physical interaction between II-III loop of the alpha1 subunit of the skeletal dihydropyridine receptor (DHPR) and ryanodine receptor (RyR). A peptide corresponding to II-III loop residues 671-690 of the skeletal DHPR (peptide A) is a high affinity activator of the RyR when it adopts an alpha-helical structure with critical basic residues aligned along one helical surface (1). Neither the structure of the full length II-III loop, or of sequences longer than 671-690 residues have been determined. Here we describe the structure and function of a 40 amino acid peptide corresponding to residues 671-710 (peptide AB) of the skeletal DHPR alpha1 subunit. This peptide contains the A region with a further 20 residues towards the C-terminus of the II-III loop. We predicted that peptide AB would strongly activate the RyR, because (a) it contains the active A sequence of basic residues and (b) it contains a greater proportion of the II-III loop. The structure of the AB peptide was determined and it was found to consist of two helical regions joined by an unstructured linker region. Surprisingly, although the structure of the A region was maintained, the 40 residue peptide was unable to release Ca2+ from skeletal SR. Strong activity was restored when four negatively charged residues in the C-terminal part of the peptide were replaced by neutral residues. The charge substitution caused minimal changes in the overall structural profile of the peptide and virtually no changes in the A portion of the peptide. The results suggest that the ability of the A region of the skeletal II-III loop to interact with the RyR could depend on the tertiary conformation of the II-III loop, which is thought to change during EC coupling.

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“…Suppression of the H # O resonance for the NOESY and DQF-COSY spectra was achieved using pulse field gradients [15,16], while a presaturation pulse was employed for the TOCSY experiments. Temperature coefficients [17] and hence the patterns of backbone hydrogen bonding were assessed by monitoring the chemical shift values of the amide backbone protons with changes in temperature (277, 285, 298 K) in the DQF-COSY experiments. Two-dimensional data were processed on a Silicon Graphics O2 workstation using Felix 98 software.…”

Section: Nmrmentioning

confidence: 99%

The three-dimensional structural surface of two beta-sheet scorpion toxins mimics that of an alpha-helical dihydropyridine receptor segment

Green

Pace

Curtis

et al. 2003

Biochemical Journal

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An alpha-helical II-III loop segment of the dihydropyridine receptor activates the ryanodine receptor calcium-release channel. We describe a novel manipulation in which this agonist's activity is increased by modifying its surface structure to resemble that of a toxin molecule. In a unique system, native beta-sheet scorpion toxins have been reported to activate skeletal muscle ryanodine receptor calcium channels with high affinity by binding to the same site as the lower-affinity alpha-helical dihydropyridine receptor segment. We increased the alignment of basic residues in the alpha-helical peptide to mimic the spatial orientation of active residues in the scorpion toxin, with a consequent 2-20-fold increase in the activity of the alpha-helical peptide. We hypothesized that, like the native peptide, the modified peptide and the scorpion toxin may bind to a common site. This was supported by (i) similar changes in ryanodine receptor channel gating induced by the native or modified alpha-helical peptide and the beta-sheet toxin, a 10-100-fold reduction in channel closed time, with a < or = 2-fold increase in open dwell time and (ii) a failure of the toxin to further activate channels activated by the peptides. These results suggest that diverse structural scaffolds can present similar conformational surface properties to target common receptor sites.

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The Multinuclear NMR Approach to Peptides

Cited by 60 publications

References 274 publications

An NMR Investigation of the Effect of Hydrogen Bonding on the Rates of Rotation about the C−N Bonds in Urea and Thiourea

An NMR Investigation of the Effect of Hydrogen Bonding on the Rates of Rotation about the C−N Bonds in Urea and Thiourea

Activating the ryanodine receptor with dihydropyridine receptor II-III loop segments: size and charge do matter

The three-dimensional structural surface of two beta-sheet scorpion toxins mimics that of an alpha-helical dihydropyridine receptor segment

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