Powe Award supports research on how enzymes enable the pathogenicity of 2 human disease...( Blacksburg Va. -- Pablo Sobrado assi...)

Blacksburg, Va. -- Pablo Sobrado, assistant professor of biochemistry (http://www.biochem.vt.edu/faculty.php?lname=Sobrado&view=yes) with the infectious disease research group at Virginia Tech, has received a Ralph E. Powe Junior Faculty Enhancement Award for his research on enzymes that are essential for infection in two important human pathogens.

Oak Ridge Associated Universities (ORAU) presents the Powe award to faculty members who are in the first two years of their tenure track as an investment in promising achievements in an important area. The award to Sobrado will support his research on the mechanism of iron acquisition by Mycobacterium tuberculosis and Aspergillus fumigatus.

Iron is essential for all life. M. tubercuolis and A. fumigatus need iron in order to replicate. The level of free iron in humans is lower than the required concentration for these pathogens to survive. To overcome this limitation, these organisms secrete molecules called siderophores to obtain iron from the host. The iron-siderophore complex is then taken by the microbes, increasing the concentration of iron to satisfy their metabolic needs and enable infection. The synthesis of siderophores in M. tuberculosis and A. fumigatus requires special enzymes (hydroxylase) that are dependent on the cofactor flavin adenine dinucleotide (FAD). The function of these enzymes is essential to form the hydroxamate potion of the siderophore, which binds the iron molecule.

"There is no information about the mechanism of action or the structure of these enzymes. Our group will be a leader in the study of these important enzymes," Sobrado said. "If we can learn how it functions, we can perhaps identify inhibitors that can be developed as antibiotics or antifungal agents," he said. "Since humans do not have siderophores, an inhibitor should not be toxic to us."