This is part of a series of two papers on gene regulation in Bacillus subtilis rRNA-tRNA operons that contain large clusters of tRNA genes. The preceding paper (Vold, B.S., Okamoto, K., Murphy, B.J., and Green, C.J. (1988) J. Biol. Chem. 263, 14480-14484) investigates the rrnB operon containing 21 tRNA genes, and this paper investigates a B. subtilis rRNA-tRNA operon containing 16 tRNA genes an...

Phylogenetic and chemical probing data indicate that a modular RNA motif, common to loop E of eucaryotic 5 S ribosomal RNA (rRNA) and the alpha-sarcin/ricin loop of 23 S rRNA, organizes the structure of multi-helix loops in 16 S and 23 S ribosomal RNAs. The motif occurs in the 3' domain of 16 S rRNA at positions 1345-1350/1372-1376 (Escherichia coli numbering), within the three-way junction loo...

A comparison of isogenic RNase III+ and RNase III- strains of Escherichia coli shows that although both synthesize precursor and mature 16 S and 23 S ribosomal RNAs, the transient rRNA species of the RNase III- strain differ from those of the RNase III+ strain. The RNase III+ strain synthesizes p16 and p23 rRNA, whereas the RNase III- strain produces unstable 17 S, 18 S, "p23," 25 S and 30 S RN...

Comparative studies of free ribosomal RNA and ribosomes were made with two probes, Mg++ ions and ethidium bromide, which interact with RNA in different ways. Mg++. E. coli 16 S rRNA and 30 S ribosomes were equilibrated with four different buffers. Equilibration required several days at 4 degrees and several hours at 37 degrees. In all buffers ribosomes bound more Mg than free rRNA, the differen...

.............................................................. 2 Chapter 1: A Golden Age of Ribosome Structural Biology ....................................................... 5 1.1 The ribosome is central to all living organisms ................... 5 1.2 30S particles can assemble independently ....................... 9 1.3 30S central domain an interesting target for detailed structural inves...