Among model organisms, bacteria hold a unique place, as both models of infection and pathogenesis, and as research tools. More to the point, molecular biology was built upon the cell walls of lowly bacteria: The processes of DNA replication, RNA transcription, and protein translation, not to mention gene regulation, were all worked out in bacteria. Those early studies provided the foundations to understanding the more complex processes in eukaryotes.
Despite their relative simplicity (bacterial genomes are about 0.1% the size of mammalian counterparts), bacteria continue to surprise researchers. Nearly 40% of the Escherichia coli genome consists of genes encoding proteins of unknown function. Recent evidence shows that some species cheat death, cannibalize their dead neighbors' DNA, and can survive a century in suspended animation. Bacteria's heyday is far from over.
FOUNDATIONS For 100-plus years, scientists have studied the workings of the intestinal bacterium E. coli. "We know more about it ...
