Eukaryote ribosomes possess a binding site for concanavalin A.

Abstract
Ribosomes prepared from chicken liver or rabbit reticulocytes bound concanavalin A in a molar ratio of approximately 1:1. This binding is to the large subunit of the eukaryote ribosomes with a Kd of 5 .times. 10-7 M (0.degree.). The binding of concanavalin A to Escherichia coli ribosomes was much less. Binding to the RNA or to possible membrane contaminants was ruled out in control experiments. Chicken liver ribosomes were labeled in vivo with 3H-labeled amino acids, purified, and dissociated in sodium dodecyl sulfate. Affinity chromatography of this preparation made it possible to isolate the small proportion of the ribosomal proteins (about 1.5%) containing the concanavalin A binding site. This protein moved as a single band during electrophoresis on polyacrylamide gels containing sodium dodecyl sulfate and showed an apparent MW of 31,000.