TY - JOUR
T1 - Genetic and comparative analyses reveal an alternative secondary structure in the region of nt 912 of Escherichia coli 16S rRNA
AU - Lodmell, J. Stephen
AU - Gutell, Robin R.
AU - Dahlberg, Albert E.
PY - 1995/11/7
Y1 - 1995/11/7
N2 - Mutations at position 912 of Escherichia coli 16S rRNA result in two notable phenotypes. The C → U transition confers resistance to streptomycin, a translational-error-inducing antibiotic, while a C → G transversion causes marked retardation of cell growth rate. Starting with the slow-growing G912 mutant, random mutagenesis was used to isolate a second site mutation that restored growth nearly to the wild-type rate. The second site mutation was identified as a G → C transversion at position 885 in 16S rRNA. Cells containing the G912 mutation had an increased doubling time, abnormal sucrose gradient ribosome/subunit profile, increased sensitivity to spectinomycin, dependence upon streptomycin for growth in the presence of spectinomycin, and slower translation rate, whereas cells with the G912/C885 double mutation were similar to wild type in these assays. Comparative analysis showed there was significant covariation between positions 912 and 885. Thus the second- site suppressor analysis, the functional assays, and the comparative data suggest that the interaction between nt 912 and nt 885 is conserved and necessary for normal ribosome function. Furthermore, the comparative data suggest that the interaction extends to include G885-G886-G887 pairing with C912-U911-C910. An alternative secondary structure element for the central domain of 16S rRNA is proposed.
AB - Mutations at position 912 of Escherichia coli 16S rRNA result in two notable phenotypes. The C → U transition confers resistance to streptomycin, a translational-error-inducing antibiotic, while a C → G transversion causes marked retardation of cell growth rate. Starting with the slow-growing G912 mutant, random mutagenesis was used to isolate a second site mutation that restored growth nearly to the wild-type rate. The second site mutation was identified as a G → C transversion at position 885 in 16S rRNA. Cells containing the G912 mutation had an increased doubling time, abnormal sucrose gradient ribosome/subunit profile, increased sensitivity to spectinomycin, dependence upon streptomycin for growth in the presence of spectinomycin, and slower translation rate, whereas cells with the G912/C885 double mutation were similar to wild type in these assays. Comparative analysis showed there was significant covariation between positions 912 and 885. Thus the second- site suppressor analysis, the functional assays, and the comparative data suggest that the interaction between nt 912 and nt 885 is conserved and necessary for normal ribosome function. Furthermore, the comparative data suggest that the interaction extends to include G885-G886-G887 pairing with C912-U911-C910. An alternative secondary structure element for the central domain of 16S rRNA is proposed.
UR - http://www.scopus.com/inward/record.url?scp=0028853679&partnerID=8YFLogxK
U2 - 10.1073/pnas.92.23.10555
DO - 10.1073/pnas.92.23.10555
M3 - Article
C2 - 7479839
AN - SCOPUS:0028853679
SN - 0027-8424
VL - 92
SP - 10555
EP - 10559
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 23
ER -