Table 1.

rRNA cleavage pseudo first-order rate constants

Metal	rRNA	k obs (10−5 s−1)	SEM (10−5 s−1)
1 mM Fe2+
	23S	67	12
	16S	25	8.2
25 mM Mg2+
	23S	5	1.1
	16S	3	0.8