Solution NMR and CD spectroscopy of an intrinsically disordered, peripheral membrane protein: evaluation of aqueous and membrane-mimetic solvent conditions for studying the conformational adaptability of the 18.5 kDa isoform of myelin basic protein (MBP).
The stability and secondary structure propensity of recombinant murine 18.5 kDa myelin basic protein (rmMBP, 176 residues) was assessed using circular dichroic and nuclear magnetic resonance spectroscopy (1H-15N HSQC experiments) to determine the optimal sample conditions for further NMR studies (i.e., resonance assignments and protein-protein interactions). Six solvent conditions were selected based on their ability to stabilise the protein, and their tractability to currently standard solution NMR methodology. Selected solvent conditions were further characterised as functions of concentration, temperature, and pH. The results of these trials indicated that 30% TFE-d2 in H2O (v/v), pH 6.5 at 300 K, and 100 mM KCl, pH 6.5 at 277 K were the best conditions to use for future solution NMR studies of MBP. Micelles of DPC were found to be inappropriate for backbone resonance assignments of rmMBP in this instance.
Libich
David S
DS
Department of Molecular and Cellular Biology, and Biophysics Interdepartmental Group, University of Guelph, 50 Stone Road East, N1G 2W1, Guelph, ON, Canada.
Harauz
George
G
D040761:Biomimetic Materials / Q000737:chemistry; D002942:Circular Dichroism / Q000379:methods*; D003198:Computer Simulation; D008051:Lipid Bilayers / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008956:Models, Chemical; D008958:Models, Molecular; D004676:Myelin Basic Protein / Q000737:chemistry* / Q000648:ultrastructure*; D011487:Protein Conformation; D020033:Protein Isoforms / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D014867:Water / Q000737:chemistry
D008051:Lipid Bilayers; D004676:Myelin Basic Protein; D020033:Protein Isoforms; D012997:Solvents; D014867:Water