UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Conformational analysis of a receptor cytoplasmic domain

Thomas, Rosalee Cara; (1994) Conformational analysis of a receptor cytoplasmic domain. Doctoral thesis (Ph.D), UCL (University College London). Green open access

[thumbnail of Conformational_analysis_of_a_r.pdf] Text
Conformational_analysis_of_a_r.pdf

Download (26MB)

Abstract

A putative cytoplasmic domain of a membrane receptor was synthesised and studied in solution by electronic circular dichroism (CD), fourier transform infrared (FTIR) and proton nuclear magnetic resonance spectroscopy (1H nmr) as part of an attempt to elucidate the three dimensional structure of a membrane receptor by summing the structures of environmentally determined domains. Circular dichroism was used to screen the range of conformations adopted by the peptide in various media prior to nmr studies of preferred conformational states. Water and 90% methanol/water were selected as convenient media to study the two predominant states identified by CD. Perturbation CD and FTIR studies and simulation of experimental CD spectra using the conformers identified by deconvolution of FTIR Amide I bands were consistent with a molecule adopting three conformations, alpha helix, beta turn and extended helix (LHE), the position of the equilibrium being dependent on temperature, solvent, pH and ionic strength but with alpha helix favoured relative to LHE in organic solvents and LHE the preferred conformer in aqueous systems. In organic solvents concentration dependent beta sheet formation was observed. In 90% methanol/water the nmr data were consistent with a locus of stable helical structure between residues (8) and (16) and population of more extended conformers relative to helical conformers toward the peptide termini. In water the data were consistent with an equilibrium between beta turn, extended helix and extended structure. The absence of long range contacts in both media was consistent with a linear molecule. All or none of the conformations identified could be important in receptor signal transduction.

Type: Thesis (Doctoral)
Qualification: Ph.D
Title: Conformational analysis of a receptor cytoplasmic domain
Open access status: An open access version is available from UCL Discovery
Language: English
Additional information: Thesis digitised by ProQuest.
URI: https://discovery.ucl.ac.uk/id/eprint/10098880
Downloads since deposit
20Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item