Table 3.

Comparison of aminoacylation of alanine and phenylalanine on k_off (min⁻¹ × 10³) from A site

tRNA	GAA anticodon				GAC anticodon
	UUC mRNA		UdUC mRNA		GUC mRNA		GdUC mRNA
	Ala-	Relative koff Ala-/Phe-	Ala-	Relative koff Ala-/Phe-	Ala-	Relative koff Ala-/Phe-	Ala-	Relative koff Ala-/Phe-
tRNA2Ala	73 (18)	8	>500	≥60	19 (3)	4	150 (37)	21
tRNA2Arg	26 (4)	4	89 (13)	12	9.1 (3.4)	1	26 (8)	4
tRNAPhe	54 (8)	6	>500	≥38	6.7 (0.9)	2	71 (21)	11
tRNA2AVal	95 (46)	11	300 (150)	27	9.7 (1.6)	2	76 (6)	12

All k_off values were measured with complementary codons. Values (± SD) are for at least three separate determinations. Ratios determined using appropriate data from Tables 1 and 2. 0.5 min⁻¹ is the upper limit of the assay.