Further physicochemical characterization of the novel human brain protein h3.
Recently we reported the isolation and partial biochemical characterization of the novel polypeptide h3 from human brain and liver. In this report, the physicochemical characterization is further established by the use of several analytical methods. The following results were obtained: the ultraviolet absorption spectrum is not influenced by pH, and the circular dichroism (CD) spectrum reveals that this protein has no alpha-helices, whereas approximately 25% of the polypeptide chain is found to be folded as a beta-pleated sheet structure. Neither the conformation of h3 as assessed by CD nor the titration kinetics of sulfhydryl groups with Ellman's reagent are affected by the presence of the ions K+, Na+, Ca2+, and Mg2+. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in a beta-mercaptoethanol gradient and Cleveland sequential SDS-PAGE showed that the frequent formation of h3 polymers and doublets, as observed earlier, is almost exclusively due to disulfide bonding.
Bollengier
F
F
Laboratorium voor Fysiopathologie, Fakulteit Geneeskunde en Farmacie, Vrije Universiteit Brussel, Belgium.
Beeckmans
S
S
Mahler
A
A
Kanarek
L
L
D000727:Androgen-Binding Protein; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002942:Circular Dichroism; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008970:Molecular Weight; D009419:Nerve Tissue Proteins; D010455:Peptides; D049488:Phosphatidylethanolamine Binding Protein; D011487:Protein Conformation; D011506:Proteins; D014466:Ultraviolet Rays
D000727:Androgen-Binding Protein; D009419:Nerve Tissue Proteins; C511482:PEBP1 protein, human; D010455:Peptides; D049488:Phosphatidylethanolamine Binding Protein; D011506:Proteins