The 23 S ribosomal RNA of Sulfolobus solfataricus (strain MT4): Sequence, structure and functional homology with other 23 S rRNAs of thermophilic, sulfur-dependent archaea

The primary and secondary structures of the 23 S ribosomal RNA of the archaeon (archeabacterium) Sulfolobus solfaxaricus strain MT4, were deduced from the sequence of the cloned gene. The structure of the 'processing stem' of the 23 S rRNA was also deduced and the position of some processing cuts was experimentally determined. Sulfolobus solfataricus 23 S rRNA was found to resemble closely in both sequence and structure the 23 S rRNAs of other thermophilic, sulphur-dependent archaea (crenarchaeota), particularly that of Desulfurococcus mobilis. However, ribosome reconstitution experiments demonstrated that the 23 S rRNAs of Sulfolobus and Desulfurococcus were not functionally interchangeable, possibly because of subtle but crucial differences in a region involved in the binding of an assembly-initiating protein.