Nicotine-Chomping Bacteria May Hold Key For Developing Anti-Smoking Drug

A bacteria that guzzles down nicotine may help people quit smoking, says a new study.

An enzyme from the Pseudomonas putida bacterium originally isolated from soil in a tobacco field consumes nicotine as its sole source of carbon and nitrogen. Researchers at The Scripps Research Institute (TSRI) said that this NicA2 enzyme can be recreated in the lab while retaining its potency, thus making it a potential candidate for drug development.

"Our research is in the early phase of drug development process, but the study tells us the enzyme has the right properties to eventually become a successful therapeutic," said Dr. Kim Janda, member of the Skaggs Institute for Chemical Biology at TSRI.

The new research offers a possible alternative to current smoking cessation aids, which are shown to fail in at least 80 to 90 percent of smokers. The enzyme therapy will destroy nicotine before it reaches the brain- depriving a person of the "reward" of nicotine that can trigger relapse into smoking.

TSRI researchers characterized the bacterial enzyme responsible for nicotine degradation and tested its potential usefulness as a therapeutic. They first combined serum (a component of blood) from mice with a dose of nicotine equivalent to one cigarette. When they added the enzyme, the nicotine's half-life dropped from two to three hours to just 9 to 15 minutes.

Janda said, "A higher dose of the enzyme-with a few chemical modifications-could reduce the half-life of nicotine even further and keep it from ever reaching the brain."

Next, the researchers subjected the enzyme to a barrage of tests to determine its practicality as a drug candidate. The enzyme stayed stable for more than 3 weeks at 98 degree Fahrenheit.

"The enzyme is also relatively stable in serum, which is important for a therapeutic candidate," said Song Xue, a TSRI graduate student and first author of the study.

Janda said the next step is to alter the enzyme's bacterial makeup, which will help mitigate potential immune liabilities and maximize its therapeutic potential. The study is published in the Journal of the American Chemical Society.

Source: Medindia