Table 2.

Levels of expression and aminoacylation

Clone	Type*	% of activity†	% of aminoacylation‡	% of expression§
Ala	6	100	91  ± 4	100
46	7-1	10  ± 0.7	86  ± 10	5  ± 3
49	7-1	6  ± 0.3	83  ± 13	13  ± 12
43	7-2	23  ± 0.7	96  ± 6	6  ± 2
25	8	4  ± 0.6	86  ± 14	9  ± 7
7	8	11  ± 3.8	66  ± 24	12  ± 3
39	9	7  ± 0.1	90  ± 10	15  ± 8
37	10	2  ± 0.2	84  ± 14	22  ± 15

^*Structural type defined in Fig. 4. 

^†Obtained by averaging β-galactosidase activity from three independent cellular extracts (21). 

^‡Determined by scanning the first lane of each clone in the autoradiogram of acid polyacrylamide gels (Fig. 3B). These values are the average of three independent experiments. 

^§Obtained from the total tRNA (tRNA + aminoacylated tRNA) in each of the two lanes of the clones. The quantity of tRNA in each band was first normalized to the quantity of 5S RNA in the same lane (internal standard) and expressed as a percentage of the tRNA_su+^Ala control (Fig. 3B). These values were obtained from three experiments.