Molecular Phylogenetics

• Protein, DNA & RNA: They all use the same 20 amino acids in their proteins and the same nucleotides in their DNA and RNA. • The handedness of the building blocks: Amino acids are always L isomers, while the ribose moieties of DNA and RNA are exclusively D isomers. • The functions of DNA and RNA in protein synthesis are very similar in all organisms within the prokaryote / eukaryote domains, while different to some extent between different domains. • Even biochemical pathways are similar among higher level eukaryotes.