title: Effect of salt concentration on immunoglobulin G structure.
abstract: An effect of salt concentration on the human myeloma immunoglobulin G structure was studied by means of circular dichroism, thermal perturbation difference spectroscopy and isoelectric focusing in a pH gradient created by a concentration gradient of glucose in borate buffer solution. Immunoglobulin G (K) Iva showed a significant shift of isoelectric point to the alkaline region as a result of the increase in salt concentration. The difference spectra indicated a change in the exposure of tyrosine residues as a result of increase in salt concentration. No changes in the circular dichroic spectra with salt concentration were observed between 205 and 250 nm. Spectral changes observed for the undigested immunoglobulin G molecule are more marked than those observed for the isolated Fab fragments.
mesh_terms: D002942:Circular Dichroism; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000302:isolation & purification; D007074:Immunoglobulin G / Q000302:isolation & purification; D009194:Myeloma Proteins / Q000302:isolation & purification; D009994:Osmolar Concentration; D011487:Protein Conformation; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature
chemical_list: D007140:Immunoglobulin Fab Fragments; D007074:Immunoglobulin G; D009194:Myeloma Proteins