TABLE 1.

Growth rate and distribution of plasmid-encoded 1406A 16S rRNA containing the sequence at position 1192 encoding either the wild type (1192C) or spectinomycin resistance (1192U)^a

16S rRNA sequence	Doubling time (min)	% Plasmid-encoded 16S rRNA
		30S	70S	Disomes	Trisomes
1406A, 1192C	42	69	56	51	50
1406A, 1192U	60	47	29	27	31

^aMutant rRNAs were expressed in E. coli strain DH1. The percent plasmid-encoded 16S rRNA in each fraction is the average of at least two experiments. Data for 1406A, 1192C are from Recht et al. (14).