Primary structures of five ribosomal proteins from the archaebacterium Halobacterium marismortui and their structural relationships to eubacterial and eukaryotic ribosomal proteins.

The complete amino acid sequences of ribosomal proteins L9, L20, L21/22, L24 and L32 from the archaebacterium Halobacterium marismortui were determined. The comparison of the sequences of these proteins with those from other organisms revealed that proteins L21/22 and L24 are homologous to ribosomal protein Yrp29 from yeast and L19 from rat, respectively, and that H. marismortui L20 is homologous to L30 from eubacteria. H. marismortui ribosomal protein L9 showed sequence homology to both L29 from yeast and L15 from eubacteria. No homologous protein was found for H. marismortui L32. These results are discussed with respect to the phylogenetic relationship between eubacteria, archaebacteria and eukaryotes.