The world’s rubber supplies are in peril, and automobile
tire producers are scrambling to seek alternative solutions.
Tom Sharkey, chairperson of the Michigan State University
Biochemistry and Molecular Biology Department, believes isoprene, a gas given off
by many trees, ferns, and mosses, could be a viable option. Some plants use it
as a mechanism to tolerate heat stress as opposed to most crops, which stay
cool through evaporation.
Sharkey’s research team already has measured rates of
isoprene emission from plants that are used by the Environmental Protection
Agency (EPA) to predict lower-atmosphere ozone levels. His team also has
created models to measure how much isoprene plants release on a global scale.
Given the amounts of isoprene made by plants, finding a way to produce a
synthetic version for the rubber industry seemed like the next logical step,
Sharkey said.
“I’ve found that isoprene research is irresistible,” he
said. “Once it was clear how much isoprene trees and plants produce and how
biologically produced isoprene could be a key ingredient in making tires, it
was natural to wonder if we could produce isoprene on a commercial scale.”
The majority of automobile tires are made of natural
rubber from latex-bearing trees. Harvesting rubber from these trees to feed the
world’s appetite for tires isn’t sustainable, Sharkey added. Since rubber is
made up of isoprene, Sharkey has worked to create a manmade version,
bio-isoprene, which can serve as an eco-friendly alternative source for
synthetic rubber production.
Other researchers have made isoprene from petroleum to
make synthetic rubber. Sharkey’s team, however, is working to produce
bio-isoprene using an enzyme he has cloned. With the enzyme, Sharkey has made
bio-isoprene using bacteria. Sharkey and his team have partnered with private
companies to scale up his research. Ultimately, he hopes this innovative
process would take in carbon dioxide and discharge bio-isoprene using only
sunlight as an energy source.
“Rubber prices are rising, and the competition for
developing synthetic rubber is heating up,” Sharkey said. “This should help
lead to effective ways to engineer bio-isoprene and ultimately keep costs low
using this renewable alternative source for rubber production.”
Sharkey’s research, which is
funded in part by the National Science Foundation, is featured in International Innovation.