Rubulose diphosphate carboxylase synthesis in Chlamydomonas reinhardii: Inhibition by chloramphenicol and stimulation by cycloheximide

Abstract

Chloramphenicol at 50 and 100 μg/ml inhibited synthesis of ribulose diphosphate carboxylase in the ac-20 mutant strain of Chlamydomonas reinhardii. Cycloheximide at 0.5 and 1.0 μg/ml significantly stimulated synthesis of this enzyme. By comparison, chloramphenicol had no effect on induction of isocitrate lyase by acetate, and cycloheximide completely inhibited this induction. The data suggest either that the carboxylase is made completely on 70S ribosomes or, less likely, that pools of subunit made on 80S ribosomes exist with long life times in the C. reinhardii cell.