Synthetic biology: Shaping life to suit human needs

Before there were engineers there were craftsmen. Craftsmen built things using parts that worked for them. If their creations wore out or broke, only they could fix them.

Before there were bioengineers breeders and horticulturists used their knowledge of animals and plants to shape dogs and horses and flowers into coveted companions and organic objets d’art.

Engineers needed standardized parts before they could build the wonders of technological civilization. Synthetic biologists, like June Medford at Colorado State University, now take standardized genomes from bacteria and other creatures and use them like bricks to build living constructs to do our bidding. In fact, the BioBricks Foundation (http://biobricks.org/) envisions “a world in which scientists and engineers work together using freely available standardized biological parts that are safe, ethical, cost effective and publicly accessible to create solutions to the problems facing humanity.”

One of the problems June Medford’s lab is tackling is using plants to monitor toxins and pollutants in the environment. In 2011, Medford and her team in the Department of Biology announced the creation of plants that change color when they encounter specific pollutants and explosives. Green plants pale to white in the presence of specific targeted materials (like explosive chemicals or airborne pathogens) serving like a stricken canary in the dangerous coal mine of modern life.

If Medford’s lab had to start from scratch crafting mutant species or analyzing entire plant genomes, their work would take forever. Today, they can rely on a growing arsenal of shared information—biobricks, if you will—available from a variety of sources. Her lab web pages list many molecular biology web tools at http://wp.natsci.colostate.edu/medfordlab/molecular-biology-web-tools/.

In March 2013 researchers at the International Open Facility Advancing Biotechnology (BIOFAB) announced, “They have, in effect, established rules for the first language for engineering gene expression, the layer between the genome and all the dynamic processes of life.” They are making available a “collection of public domain DNA parts that greatly increases the reliability and precision by which biology can be engineered.” Such collections give labs like Medford’s tested and reliable parts to build their more elaborate biological constructs.

The possibilities for synthetic biology in transforming our world seem endless and astounding. Living systems possess the software to create nearly anything we might want from fuel, to food, to living cities capable of maintaining all the services their inhabitants might need—as long as they are properly cared for.

In November 2012, Medford’s lab received a $2 million grant from the U.S. Department of Energy to produce a biological control system for bioenergy crops. “Many plants currently used for biofuel production,” said Medford, “present serious challenges in terms of biomass and the energy needed to convert the material into useable fuel. By reengineering existing metabolic pathways, we could improve a plant’s photosynthetic capabilities and increase biomass, or modify natural enzymes so the biomass is easier to process.”

Other labs have developed techniques for inserting petroleum-producing genes in the common intestinal bacterium E. coli to bypass nature’s much longer “crush and bake” procedure. Science reporter Rebecca Morelle reported in an April 22, 2013 press release for BBC News (http://www.bbc.co.uk/news/science-environment-22253746) that John Love, a synthetic biologist from the University of Exeter, had developed a strain of E. coli that can convert sugar directly to diesel fuel. “They are bio-fossil-fuels if you like,” he said. The problems remaining for commercial production lie in ramping up production. Currently, it would take 100 liters of bacteria to produce a teaspoon full of fuel.

Synthetic biologists envision evening grander schemes, from curing cancer to growing houses and even entire cities. Swiss-born billionaire, Hansjörg Wyss, and Harvard Business school graduate donated $125 million to his alma mater to create the Wyss Institute for Biologically Inspired Engineering. There, under the guidance of Donald Ingber, researchers from various scientific disciplines take cues from nature to develop startling technologies. Bioengineer David Mooney, for example, impregnated porous plastic disks with mouse tumor extracts. The disks, when implanted in mouse skin, stimulated mice to produce an immune response that led to complete regression of melanoma in 40 percent of the mice.

Architects at MIT and Columbia University continue to work on ideas for building houses—even entire cities—by growing them like exotic plants. Mitchell Joachim believes he could make a “Fab Tree Hab,” creating the basic framework with a gardening method called pleaching that involves weaving together young trees into desired shapes and sculpting the rest with soil, clay, straw and other plants. Other architects want to enlist bacteria to create self-healing building material out of porous lattices, lighting from luminescent bacteria, skyscraper vertical farms where every floor is a solar-powered greenhouse, and systems that would recycle water and wastes and neutralize toxins. Cities could become ecosystems that would be self-sustaining when nurtured properly.

“The more ambitious projects,” said Medford, “are likely 20-plus years in the future, but others such as improved biofuel development may only be five to seven years away.”

Bioengineers are poised to take the tools forged by life over the eons and put them to work for humans. Perhaps growing green homes, powering our tools with bacterial waste, watching plants flash color warnings, and coaxing our bodies to respond properly to both friendly and hostile microbes will put us all in closer touch with the living world on which we all depend.