NEW YORK (May 10, 2010) -- Tuberculosis (TB) has been present in humans since ancient times. The origins of the disease date back to the first domestication of cattle, and skeletal remains show prehistoric humans (4,000 B.C.) had TB. Although relatively rare in the United States, it is the single leading bacterial cause of death worldwide. Approximately 8 million people are infected each year and 2 million people die from TB.
The cause of tuberculosis is Mycobacterium tuberculosis (Mtb), a slow-growing aerobic bacterium that divides every 16 to 20 hours. Scientists know that carbon metabolism plays a significant role in the ability of Mtb to replicate and persist in the body and that fatty acids are the major source of carbon and energy during infection. However, the specific enzymes required for the metabolism of fatty acids have not been completely defined.
New research conducted at Weill Cornell Medical College and published online in the Proceedings of the National Academy of Sciences (PNAS) sheds light on a previously unrecognized aspect of fatty acid metabolism that could potentially lead to new targets for drug therapy. A team led by Dr. Sabine Ehrt, professor of microbiology and immunology at Weill Cornell Medical College, reported that Mtb relies primarily on gluconeogenic substrates for in vivo growth and persistence, and that phosphoenolpyruvate carboxykinase (PEPCK) plays a pivotal role in the growth and survival of Mtb during infections in mice, making PEPCK a potential target for drugs that fight tuberculosis.
Dr. Ehrt and her colleagues found a way to silence the gene encoding PEPCK in Mtb during mouse infections to assess the importance of gluconeogenesis for Mtb's ability to maintain a chronic infection. According to Dr. Ehrt, "Silencing a gene when the pathogen is not or only slowly replicating, after an infection has established, is an important tool for studying diseases such as TB, which can b
|Contact: Andrew Klein|
New York- Presbyterian Hospital/Weill Cornell Medical Center/Weill Cornell Medical College