Protein composition of Lp(a) lipoprotein from human plasma.
The apolipoprotein composition of purified human Lp(a) lipoprotein was investigated by SDS--polyacrylamide gel electrophoresis and immunochemically. The lipoprotein contains two different polypeptides. One is identical by its app. Mr of approximately 250 000 and immunologically with apolipoprotein B of LDL (B-100). The other polypeptide has a higher app. Mr (approximately 350 000) and stains strongly with the periodate-Schiff's reagent. This high-Mr glycoprotein contains the specific Lp(a) immunoreactivity but does not react with antibodies against apo B. Apo B and Lp(a)-protein seem to be linked by disulfide bonds in the native lipoprotein. The unreduced detergent delipidized protein moiety from Lp(a) lipoprotein shows a single band of Mr approximately 700 000 in SDS--polyacrylamide gel electrophoresis and the immunoprecipitates formed against anti-Lp(a) and anti-apo B by the unreduced protein show a reaction of immunological identity.
D001053:Apolipoproteins / Q000032:analysis; D001055:Apolipoproteins B; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D005779:Immunodiffusion; D017270:Lipoprotein(a); D008074:Lipoproteins / Q000097:blood*; D008970:Molecular Weight; D011506:Proteins / Q000032:analysis
D001053:Apolipoproteins; D001055:Apolipoproteins B; D017270:Lipoprotein(a); D008074:Lipoproteins; D011506:Proteins