TABLE 3.

Nucleotide specificity for three-factor-dependent subunits formation^a

Nucleotides	70S converted to subunits (%)	Activity (%)
a) GTP	68.4	100.0
b) No nucleotide	14.2	20.7
c) GDP	20.4	29.9
d) GMPPCP	17.2	25.1
e) ATP	18.9	27.7

^aW-ribosomes were incubated with RRF (1 μM), EF-G (1 μM), and IF3 (4.5 μM) in the presence of 0.36 mM GTP or GDP or GMPPCP, or ATP at 30°C for 15 min in 275 μL of conventional buffer R, and sedimentation behavior of ribosomes was analyzed as in Table 1.