This study will investigate the solution structure and folding of bovine myelin basic protein species that have been separated into the nonphosphorylated, one phosphate residue, two phosphate residue and three phosphate residue species. Each one of the four myelin basic protein charge isomers will be reacted with the crosslinking agents 2-(p-nitrophenyl)allyltrimethylammonium iodide and 2-(p-nitrophenyl)allyl-4-nitro-3-carboxyphenyl sulfide. These reagents react with lysine residues via Michael addition to give products of thermodynamic control rather than kinetic control as produced by other crosslinking agents. The intra and inter molecularly crosslinked protein will be separated and the lysine residues involved will be determined via tryptic peptide mapping and amino acid analysis. Parallel experiments using ethylene glycol bis (succinimidyl succinate) to give the products of kinetic control will also be carried out. Analysis of the crosslinking results should permit a determination of the proximal lysine residues in the folded protein. The influence of the phosphate residues on the secondary structure and folding of the protein will be studied using Raman and FT-IR spectroscopy. Also, the effect of pH, ionic strength and solvent on the diffusion coefficient and radius of gyration will be determined using quasielastic light scattering. The results of this study will assist in understanding the role of structure in antigenicity of this protein. In turn that understanding will assist in helping to understand the role of the protein in Multiple Sclerosis and EAE. The data will also assist in understanding the role of this protein in the myelin membrane.
Caamano, C A; Azcurra, J M; Sellinger, O Z et al. (1989) Kinetics of carboxylmethylation of the charge isoforms of myelin basic protein by protein methyltransferase II. J Neurochem 53:1883-8 |
Caamano, C A; Zand, R (1989) Homologous sequences in cholera toxin A and B subunits to peptide domains in myelin basic protein. FEBS Lett 252:88-90 |
Caamano, C A; Zand, R (1989) Resolution and solution behavior of crosslinked myelin basic protein. Biochem Int 18:1245-51 |