Isolation of human alpha-fetoprotein in two fractionation steps and demonstration of homogeneity.
Human alpha-fetoprotein (hAFP) has been isolated from cord serum in 40% yield using an isolation procedure consisting of only two major steps: affinity chromatography followed by preparative polyacrylamide gel electrophoresis (PAGE). The final product appeared homogeneous on the basis of five independent criteria for purity. Sodium dodecyl sulfate gel electrophoresis (SDS-PAGE) demonstrated a single polypeptide chain with molecular weight of 71,000. The protein exhibited an apparent isoelectric point (pI') of 4.85, molecular radius of 3.0 nm and a valence (net H+/molecule) of 21.9 derived from computation of analytical PAGE data. The two-step isolation procedure made it possible for a single operator to isolate milligram amounts of hAFP in a matter of weeks.
D002021:Buffers; D002846:Chromatography, Affinity / Q000379:methods; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D006801:Humans; D007525:Isoelectric Focusing; D007526:Isoelectric Point; D008970:Molecular Weight; D011487:Protein Conformation; D000509:alpha-Fetoproteins / Q000302:isolation & purification*
D002021:Buffers; D000509:alpha-Fetoproteins