A cheap, renewable, environmentally friendly energy source is the goal not just of many engineers, but also of some biotechnologists. J. Craig Venter, founder of Celera Genomics, which raced against the Human Genome Project to sequence the entire human complement of DNA, has set up the Institute for Biological Energy Alternatives, a nonprofit laboratory that is hunting for ways microbes can provide energy and clean the environment.

Researchers have been experimenting with bacteria that can produce fuels such as hydrogen and methane, as well as those that can remove carbon dioxide, a major greenhouse gas, from the air. But it's difficult or impossible to grow many of the most promising organisms in a lab. So Venter plans to use the latest genetic-engineering tools to amplify these bacteria's gas-producing and air-cleaning traits and transfer them to other microbes that are easier to work with, or eventually to build entirely new organisms.