Charakterisierung von Proteinen aus Leber- und Hepatom-Ribosomen durch Polyacrylamid-Gelelektrophorese

Abstract

Proteins isolated with 2 M LiCl from purified rat liver ribosomes can be separated electrophoretically on polyacrylamide gel into 24 fractions moving cationically at pH 2. In the proteins from crude ribosomal preparations, some bands of acidic proteins are additionally present. These acidic proteins can be removed by washing or by precipitation with MgCl₂, corresponding to a loss of total proteins of about 5 — 10%, without impairing the proteosynthetic activity of the ribosomes. The proteins of the large subunit are also separated into 24 bands which are qualitatively identical to those of the 80 S-ribosomes. Only 18 bands, however, are found in the proteins from the small subunit. Proteins from hepatoma ribosomes and their subunits do not differ from those isolated from liver ribosomes.