title: Structure of synthetic unmethylated 16S ribosomal RNA as purified RNA and in reconstituted 30S ribosomal subunits.
abstract: 16S ribosomal RNA was made by in vitro transcription of a cloned gene, and its structure was compared to authentic 16S ribosomal RNA. The comparison was made by subjecting the two types of 16S rRNA to chemical reagents that react specifically with unpaired bases and determining the extent of reaction by reverse transcription and gel electrophoresis of the cDNA. In solution, the rRNAs were indistinguishable in their pattern of reactivity, except for a difference at A1408 and many differences in the region between residues 470 and 562. When the 16S rRNAs were reconstituted into 30S ribosomal subunits, these reactivity differences were absent. When the synthetic 16S rRNA was reconstituted into 30S subunits and then extracted and tested in solution, its pattern of chemical reactivity in the 470-562 region was the same as authentic 16S rRNA, but differences in the 1408-1410 region persisted. This study indicates that the synthetic 16S rRNA has a secondary structure in solution similar to a native secondary structure except in two regions, one apparently incorrectly folded during synthesis and the other in which nucleotides which are normally methylated in authentic 16S rRNA may be responsible for a structural difference.
authors.affiliation: E. A. Doisy Department of Biochemistry and Molecular Biology, St. Louis University Medical Center, Missouri 63104.
authors.forename: G
authors.initials: G
authors.lastname: Ericson
authors.forename: K
authors.initials: K
authors.lastname: Chevli
authors.forename: P
authors.initials: P
authors.lastname: Wollenzien
mesh_terms: D001483:Base Sequence; D004275:DNA, Ribosomal / Q000235:genetics*; D015180:Electrophoresis, Gel, Two-Dimensional; D004926:Escherichia coli / Q000235:genetics*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D012335:RNA, Ribosomal / Q000235:genetics*; D012336:RNA, Ribosomal, 16S / Q000138:chemical synthesis / Q000235:genetics* / Q000302:isolation & purification; D012269:Ribosomal Proteins / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D004275:DNA, Ribosomal; D012335:RNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D012269:Ribosomal Proteins