September 12, 2001

Using Bacteria To Manufacture Left-Handed AIDS Drug

from the Daily University Science News



Using bacteria as factories to produce drugs could be safer, cheaper and more efficient than traditional chemical manufacturing methods, experts heard today during the bi-annual meeting of the Society for General Microbiology at the University of East Anglia in the UK.

“Chiral drugs are important in the treatment of many illnesses including heart disease, breast cancer and AIDS. Traditional approaches for the manufacture of these chemicals are expensive, have low yield and require toxic chemicals.

"We have modified Rhodococcus bacteria to synthesize a key intermediate compound in the manufacture of the HIV drug Crixivan®,” said Professor Greg Stephanopoulos of the Massachusetts Institute of Technology, USA.

When it comes to some naturally occurring molecules, the choice of mirror image is critical, and being left-handed is highly beneficial.

The occurrence of handedness in chemicals, called chirality, has big implications for the chemical synthesis of food and drugs. The sugar glucose, for example, is a left-handed molecule, whereas the right-handed mirror image is not sweet at all.

"The big problem with traditional industrial methods is that they can also produce mirror images of the drugs that have the same chemical composition but are not biologically active. This means that you get a low yield of the desired product. But we can grow bacteria in fermentors that produce only the desired type of molecule,” says Prof. Stephanopoulos.

Furthermore, says Prof. Stephanopoulos, “the Rhodococcus system that we have developed is broadly applicable for the production of any number of other drugs.”

Professor Stephanopoulos, of the Dept. of Chemical Engineering at MIT, titled his conference presentation "After a decade of progress, an expanded role for Metabolic Engineering."

The Society for General Microbiology in the UK is the largest microbiology society in Europe, and has over 5,500 members worldwide. The Society provides a common meeting ground for scientists working in research and in fields with applications in microbiology, including medicine, veterinary medicine, pharmaceuticals, industry, agriculture, food, the environment and education.

[Contact: Professor Greg Stephanopoulos]