title: Chemical modification of 5S and 4.5S rRNAs in situ in spinach chloroplast ribosomes.
abstract: Spinach chloroplast ribosomes and 50S subunits were reacted with diethylpyrocarbonate under conditions in which their gross structures can be maintained. 5S and 4.5S rRNAs were isolated from such modified particles and the modified adenine residues of these rRNAs were identified by using gel sequencing method. The accessible sites of 5S rRNA in 50S subunits to the reagent were found to be A15, A40 and A89 and that of 5S rRNA in whole ribosomes was restricted to A89. In the case of 4.5S rRNA, A33 was exclusively modified in ribosomes or 50S subunits.
mesh_terms: D002736:Chloroplasts / Q000502:physiology* / Q000648:ultrastructure; D009690:Nucleic Acid Conformation; D010944:Plants; D012335:RNA, Ribosomal; D012270:Ribosomes / Q000648:ultrastructure*
chemical_list: D012335:RNA, Ribosomal