Untitled

Gente, Giacomo; Mesa, Camillo La

doi:10.1023/a:1005147318013

Cited by 52 publications

(41 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The experimental dielectric constant of 35% ethanol (e 5 58) was used in the electrostatic part of the force field. 19,20 Peptide-solvent proton-proton NOE and ROE intermolecular cross-relaxation parameters (r NOE HH , r ROE HH ) were determined by the procedures previously described. [21][22][23] Observed NOE and ROE peak intensities for several values of the mixing time (t mix ) were fit to the empirical function A 3 t mix 1 B 3 (t mix ) 2 , with the coefficient A taken as the initial slope of the data and used to compute the corresponding cross-relaxation parameter.…”

Section: And Nmr Spectroscopymentioning

confidence: 99%

Solvent interactions with the Trp‐cage peptide in 35% ethanol–water

Neuman

Gerig

2008

Biopolymers

View full text Add to dashboard Cite

Intermolecular NOE experiments have been used to explore interactions of water and ethanol molecules in 35% ethanol/65% water (v/v) with the peptide Trp-cage at temperatures from 5 to 25 degrees C. Magnetic dipole-dipole cross-relaxation terms sigma(HH) (NOE) and sigma(HH) (ROE) for interaction of solvent components with spins of the peptide suggest that ethanol molecules associate with backbone atoms for times of the order of nanoseconds at 5 degrees C. Formation of peptide-ethanol complexes can also account for the larger-than-expected values of cross-relaxation terms at higher temperatures. Hydrocarbon side chains of the peptide do not appear to experience such interactions with ethanol. Cross relaxation resulting from water-peptide interactions are consistent with long-lived water interactions with the backbone atoms. Water cross relaxation with nonpolar side chains of the peptide (Leu2, Ile4, Leu7, and proline residues) are only those expected for bulk solvent. However, long-lived association of both water and ethanol with the polar side chains of Tyr3 and Trp6 is indicated by the data.

show abstract

Section: And Nmr Spectroscopymentioning

confidence: 99%

Solvent interactions with the Trp‐cage peptide in 35% ethanol–water

Neuman

Gerig

2008

Biopolymers

View full text Add to dashboard Cite

show abstract

“…Although the NMC molecular size scarcely changed in presence of 60% TFE (Figure 1C), the τc increased ~3 times as a result of the enlarged viscosity of the TFE/water mixture. [38] Furthermore, the τc of the NMC-SDS micelle complex is ~8 times bigger than that of free NMC, which can be ascribed to the resulting high molecular weight complex. In addition, this τc value is also ~1ns bigger than that of free SDS micelles, [39] which points to the formation of 1:1 NMC-SDS micelle complex.…”

Section: The α-Helical Folding and The Micelle Binding Effects On Thementioning

confidence: 99%

“…[47] The addition of 60% TFE enlarged the τc ~3 times, which is attributed to an increased solvent viscosity typical of the TFE/water mixtures [38] and not to changes in the peptide size. [47b,48] The τc of the NMC-SDS complex was ~1ns bigger than that of free SDS micelles proving that the NMC slightly reduces the micellar tumbling rate as a result of the formation of 1:1 complex; the stoichiometry mainly observed in peptide-micelle complexes.…”

mentioning

confidence: 99%

“…The 15 N-relaxation data acquired at 60% TFE could be affected by the increase in the viscosity (Δη~1cp at 25ºC [38] ). However, data comparing the NMR dynamics of the Escherichia coli orthologue of frataxin (CyaY) in water (η~0.89cp [38] ) and in hen egg white (η~4cp [52] ) prove that viscosity does not affect the CyaY fold nor the HET-NOE values, but notably decreased and increased the R1 and R2 values, respectively.…”

mentioning

confidence: 99%

“…However, data comparing the NMR dynamics of the Escherichia coli orthologue of frataxin (CyaY) in water (η~0.89cp [38] ) and in hen egg white (η~4cp [52] ) prove that viscosity does not affect the CyaY fold nor the HET-NOE values, but notably decreased and increased the R1 and R2 values, respectively. [53] The viscosity change scarcely affected the S 2 values of CyaY, calculated assuming an axially symmetric diffusion model (ΔS 2 av~0.06) ( Figure S6).…”

mentioning

confidence: 99%

See 2 more Smart Citations

Conformational ensembles of neuromedin C reveal a progressive coil-helix transition within a binding-induced folding mechanism

et al. 2015

View full text Add to dashboard Cite

Abstract:Neuromedin C (NMC) is a peptide that regulates various processes in the central nervous system and gastrointestinal tract through its interaction with the bombesin receptor subtype-2 (BB2R). Hence, BB2R antagonists hold potential to treat disorders that occur as a result of NMC dysfunction or misregulation. However, their efficient design requires a detailed understanding of the structural features of NMC, which hitherto are unknown. Here we describe the conformational ensembles of NMC in aqueous solution, at five different TFE concentrations to decode its folding pathway, and under its SDS micelle bound state that likely resembles the receptor-triggered conformation. NMC displays a disordered but well-defined backbone architecture that undergoes a progressive coil-helix transition with increasing TFE concentrations, first at the C-terminus and then at the N-terminus. NMC also adopts a C-terminal α-helical conformation upon binding to SDS micelles. This micelle binding is directed by hydrophobic interactions that concur with the unfavorable deprotonation of His8 and its further insertion into the micelle. Moreover, NMR relaxation data reveal that the acquisition of the micelle bound α-helical conformation constrains the NMC flexibility more than the confinement itself. This comprehensive study of the structural behavior of NMC provides essential mechanistic information for the development of new Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporationtherapeutics to treat neurological, cancer-related or eating disorders.Author Comments: Dear Editor,We would like to submit our manuscript entitled "Conformational ensembles of neuromedin C reveal a progressive coil-helix transition within a binding-induced folding mechanism" to be considered for publication in Chemistry A-European Journal.Neuromedin C (NMC) is a decapeptide that regulates different biological process in the central nervous system and in the gastrointestinal tract. For instance, NMC modulates appetite, participates in neurotransmission, and regulates growth and differentiation of tumors. All these processes are mediated through its interaction with the subtype-2 bombesin receptor (BB2R), which is a member of the G-protein coupled receptor superfamily. Thus, BB2R antagonists are considered as potential therapeutics and their efficient design will benefit from the understanding of the structural features of NMC.At present, the available structural information on NMC is very limited. Therefore, we provide a comprehensive description of the structural behavior of NMC in the accompanying manuscript. Different biophysical techniques (nuclear magnetic resonance, fluorescence, circular dichroism and isothermal titration calorimetry) were used to characterize the conformations of NMC in aqueous solution. We calculated the solution structure of NMC at increasing TFE concentrations in order to describe at residue level the pathway involved in its coil-helix transition, a process that likely mimics the receptor interaction. T...

show abstract

Solvents for Ions

Marcus

2015

Ions in Solution and Their Solvation

View full text Add to dashboard Cite

Untitled

Cited by 52 publications

References 17 publications

Solvent interactions with the Trp‐cage peptide in 35% ethanol–water

Solvent interactions with the Trp‐cage peptide in 35% ethanol–water

Conformational ensembles of neuromedin C reveal a progressive coil-helix transition within a binding-induced folding mechanism

Solvents for Ions

Contact Info

Product

Resources

About