title: Cationization of bovine serum albumin alters its conformation as well as its charge.
abstract: The molecular charge on bovine serum albumin (BSA) was modified by substituting carboxyl groups on the protein with ethylenediamine, thereby producing a highly cationic derivative with a pI of 9.3 to 9.5. Gel-filtration studies showed that the molecular weight of BSA was not significantly altered after cationization. When the cationized BSA was administered to rabbits using a chronic serum sickness schedule of injections, the animals developed a membranous glomerulopathy similar to the human disease, except that approximately one-third of the animals also showed focal and segmental endocapillary proliferation. Comparison of the circular dichroism spectra of native and cationized BSA showed that the substitution of the carboxyl groups resulted in a 50% reduction in the alpha-helical content of the native molecule. This conformational change should be considered as a possible determinant of the different immune response and immunopathology associated with the cationized molecule compared with native BSA.
authors.affiliation: Department of Histopathology, United Medical School of Guy's Hospital, London, United Kingdom.
authors.forename: P S
authors.initials: PS
authors.lastname: Bass
authors.forename: A F
authors.initials: AF
authors.lastname: Drake
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.forename: J H
authors.initials: JH
authors.lastname: Thomas
authors.forename: D R
authors.initials: DR
authors.lastname: Davies
mesh_terms: D000818:Animals; D002412:Cations; D055598:Chemical Phenomena; D002621:Chemistry; D005029:Ethylenediamines; D015433:Glomerulonephritis, Membranous / Q000139:chemically induced*; D007678:Kidney Glomerulus / Q000187:drug effects*; D008297:Male; D008970:Molecular Weight; D011817:Rabbits; D012710:Serum Albumin, Bovine / Q000138:chemical synthesis* / Q000378:metabolism / Q000494:pharmacology
chemical_list: D002412:Cations; D005029:Ethylenediamines; D012710:Serum Albumin, Bovine; C031234:ethylenediamine