Discovery of Tuberculosis Bacterium Enzyme Paves Way for New TB DrugsMarch 30, 2009A team of University of Maryland scientists has paved the way for the development of new drug therapies to combat active and asymptomatic (latent) tuberculosis infections by characterizing the unique structure and mechanism of an enzyme in M. tuberculosis, the bacterium that causes the disease. Assistant Professor of Chemistry and Biochemistry Barbara Gerratana, in the university's College of Chemical and Life Sciences, led the research team, which included her graduate student Melissa Resto and Assistant Professor Nicole LaRonde-LeBlanc. "The NAD+ synthetase enzyme that our study describes is absolutely essential for the survival of the tuberculosis bacteria and an important drug target. We can now use the information we have about its structure and mechanism to develop inhibitors for this enzyme," Gerratana explained. The study, titled "Regulation of active site coupling in glutamine-dependent NAD+ synthetase," was published in on March 8, 2009 in Nature Structural & Molecular Biology. The development of new drugs to combat tuberculosis (TB) has become urgent, as strains of TB resistant to all major anti-TB drugs have emerged worldwide. The World Health Organization estimates that one third of the world's population is asymptomatically infected with TB and that ten percent will eventually develop the disease. According to other leading TB researchers, these new findings from Gerratana and her colleagues will be extremely valuable for the design of structure-based inhibitors specific for M. tuberculosis NAD+ synthetase and may lead to the development of new drugs to combat and eliminate the disease. "NadE [NAD+ synthetase] represents one of a small handful of TB drug targets that has iron-clad validation, the lack of a crystal structure was the only serious impediment to drug development and this study represents a hugely important step forward" said Clifton E. Barry, Chief of the Tuberculosis Research Section of the Intramural Research Division of the National Institute of Allergy and Infectious Diseases. "Inhibiting NadE even kills non-replicating cells, so this discovery may well benefit the one-third of the human population that carries latent bacteria." NAD+ synthetase is responsible for making NAD+, a coenzyme found in all living cells that is involved in regulating many cellular processes and in reduction-oxidation metabolic reactions. More than one biosynthetic pathway is usually involved in NAD+ production. In humans, NAD+ can be obtained through several different complex pathways, and not all of the pathways utilize NAD+ synthetase to produce NAD+. Unlike in humans, however, there are only two pathways involved in producing NAD+ in the tuberculosis bacterium and both depend on the activity of NAD+ synthetase to obtain NAD+. "We are optimistic about the potential for developing new drugs that will effectively target this enzyme in TB and minimize side effects to humans, since we have NAD+ biosynthetic pathways that are independent of the NAD+ synthetase activity," Gerratana said. The World Health Organization reports that a new instance of TB infection occurs every second. Current treatment of tuberculosis targets the active tuberculosis bacterium and has little effect on the non-replicating bacterium."If we don't tackle latent tuberculosis, this disease will not be eradicated," Gerratana said. Regulation of active site coupling in glutamine-dependent NAD+ synthetase was written by Nicole LaRonde-LeBlanc, Melissa Resto, and Barbara Gerratana. This work was supported by a PRF grant from the American Chemical Society to B.G. and by start-up funds to B.G. and N.L.L. from the Dept. of Chemistry and Biochemistry, University of Maryland , College Park . University of Maryland |
|||||||||||||||||||||
| Related Tuberculosis Current Events and Tuberculosis News Articles There's a speed limit to the pace of evolution, Penn biologists say Researchers at the University of Pennsylvania have developed a theoretical model that informs the understanding of evolution and determines how quickly an organism will evolve using a catalogue of "evolutionary speed limits." Cell phones become handheld tools for global development Mobile phones are on the verge of becoming powerful tools to collect data on many issues, ranging from global health to the environment. Will genomics help prevent the next pandemic? This week, the Public Library of Science, an open-access publisher, presents the "Genomics of Emerging Infectious Disease," a collection of essays, perspectives, and reviews that explores how genomics-with all its associated tools and techniques-can provide insights into our understanding of emerging infectious disease. Exon-skipping drug prevents muscle wasting, maintains muscle function in dystrophin deficient mice An exon skipping PPMO has demonstrated dramatic effects in the prevention and treatment of severely affected, dystrophin and utrophin-deficient mice, preventing severe deterioration of the treated animals and extending their lifespan. Scientists take step toward simple and portable tuberculosis tests for developing world Two billion people worldwide carry the pathogen that causes tuberculosis (TB), and most of them do not even know they are infected. This is because some 90 percent of people with TB have "latent" infections. They have no symptoms, they can't spread the disease to others and the bug remains dormant in their lungs -- often for years. High mortality rates may explain small body size A new study suggests that high mortality rates in small-bodied people, commonly known as pygmies, may be part of the reason for their small stature. Iowa State University researcher uncovers potential key to curing tuberculosis Researchers at Iowa State University have identified an enzyme that helps make tuberculosis resistant to a human's natural defense system. Researchers have also found a method to possibly neutralize that enzyme, which may someday lead to a cure for tuberculosis. U-M study: Life and death during the Great Depression The Great Depression had a silver lining: During that hard time, U.S. life expectancy actually increased by 6.2 years, according to a University of Michigan study published in the current issue of the Proceedings of the National Academy of Sciences. New test quickly ID's active TB in smear-negative patients Active tuberculosis can be rapidly identified in patients with negative sputum tests by a new method, according to European researchers. Active tuberculosis (TB) is the seventh-leading cause of death worldwide, and while the diagnosis of active TB can be rapidly established when the bacteria can be identified on sputum microscopy, in about half of all cases, the TB bacterium cannot be detected, making another diagnostic option critical in efforts to control the spread of TB. Weill Cornell Researchers Discover New Anti-Tuberculosis (TB) Compounds Attempts to eradicate tuberculosis (TB) are stymied by the fact that the disease-causing bacteria have a sophisticated mechanism for surviving dormant in infected cells. More Tuberculosis Current Events and Tuberculosis News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||