
Fractionation of C. reinhardtii tRNA. 75Se-selenocysteyl-tRNA[Ser]Sec was obtained by labeling C. reinhardtii cells, extracting tRNA, mixing it with a larger amount of total C. reinhardtii tRNA, chromatographing the mixture over an RPC-5 column, pooling column fractions from the two peaks of 75Se-selenocysteyl-tRNA[Ser]Sec as shown in the figure, and preparing the pooled fractions for sequencing as given in Materials and Methods. (Closed circles) 75Se radioactivity; (closed diamonds) absorbance at 260 nm.










