Molecular sleuths track evolution through the ribosome
A new study of the ribosome, the cell's protein-building machinery, sheds
light on the oldest branches of the evolutionary tree of life and suggests
that differences in ribosomal structure between the three main branches of
that tree are "molecular fossils" of the early evolution of protein
synthesis.

The new analysis, from researchers at the University of Illinois, reveals
that key regions of the ribosome differ between bacteria and archaea,
microbes that the researchers say are genetically closer to eukarya, the
domain of life that includes humans. The study appears this week in the
Proceedings of the National Academy of Sciences.