Scientist teaching bacteria to eat caffeine

Link : http://uk.news.yahoo.com/041015/80/f4mjh.html


NEW YORK (Reuters) - In what could be a page taken from a science fiction novel, a scientist in his laboratory is trying to teach bacteria how to devour and destroy the caffeine contained in a coffee plant.


If successful, which the scientist says is probably years away, the experiment may yield a naturally decaffeinated brew that could have a richer and deeper taste than the decaf fare currently available.


"One of the reasons that coffee has a lot of caffeine is that coffee plants synthesise caffeine very quickly, but they break it down very slowly," said Justin Gallivan, a chemist at Emory University in Atlanta.


"We would like to develop bacteria that can break down caffeine quickly. To do this, we wanted to make the bacteria depend on the breakdown product of caffeine for their survival," he explained.


Gallivan and graduate student Shawn Desai have found a way to couple the lives of bacteria to the presence of theophylline, a compound that is produced by the breakdown of caffeine in coffee and tea plants and known for its use in treating asthma.


Their research appears in the October 20 edition of the Journal of the American Chemical Society.


Most decaffeinated coffee is made by a chemical solvent that absorbs the caffeine from the bean. A so-called "Swiss water process" uses hot water and steam to remove the caffeine from the bean, and is common in gourmet and organic brands.


Even though it is a multi-billion dollar industry, decaffeinated coffee makes up just about 10 percent of the worldwide coffee market. Gallivan said the market would expand if natural grown decaffeinated coffee plants improve the taste of decaf coffee.


Gallivan said his team plans to supply the bacteria with caffeine, and thousands of different genes from a coffee plant.


"These bacteria are addicted to theophylline -- they depend on it for their survival, but they don't know how to make it themselves. We would like to teach the bacteria to make the theophylline they need by breaking down caffeine," he said.


The bacteria that take up the gene that converts caffeine to the theophylline will survive, and Emory scientists hope to isolate this gene and make it break caffeine down faster.


"Since the bacteria depend on theophylline for survival, they will be partners in the process," he said.


Gallivan said he was unaware of any produced beverage from low-caffeine coffee plants that have been either discovered or engineered. He said his work was still far off from spawning an actual product.


So coffee drinkers who love their caffeine buzz can take heart.


"Don't expect good-tasting naturally decaffeinated coffee anytime soon. There are many hurdles to overcome. As a scientist, I am excited about the future. But as a caffeine addict, I'm not in a hurry to solve this."