will increase the number of targets for pharmaceuticals, and will increase the numbers of points of intervention in cell functioning. (2) Better understanding of regulatory networks will also help in modifying cell function in ways that potentially can be useful in addressing mission needs. (3) Exploring functional diversity will add to the limited repertoire of microbial mechanisms for adapting to a variety of environments and for interfacing with the spectrum of substances, both organic and inorganic, that microbes encounter. After all, microbes have been on earth for more than 3.5 billion years and have learned to thrive in many niches exploiting available energy sources and nutrients. (4) The ability to model cell behavior in silico will generate many testable hypotheses (much as gene sequences do today) for a much deeper understanding of cell structure and function.
Although enormous value is still to be gained from continued sequencing, we now need to learn how to put the biological “parts” together into understandings of cell processes and functions. The familiar (and very successful) reductionist approach needs to be supplemented by a new “reconstructionist” approach that recognizes that complex biological systems are more than the simple sum of their parts. Starting with “simple” microbial cells and being aware that multicellular life evolved from unicellular forms, we can expect this to be a massive challenge for all of biology.