Enzyme in Tuberculosis Bacteria May Be Drug Target

Researchers have characterized the enzyme produced by the LipB gene of the tuberculosis bacteria Mycobacterium tuberculosis and speculate that it may be an attractive target for drugs to control the organism.

LipB encodes for octanoyl-[acyl carrier protein]-protein acyltransferase, an enzyme that is considerably overexpressed in cells infected by multidrug-resistant forms of M tuberculosis. Investigators at the European Molecular Biology Laboratory (Hamburg, Germany) and the Max Planck Institute for Infection Biology (Berlin, Germany) resolved the crystal structure of the LipB protein at atomic resolution, showing an unexpected thioether-linked active site complex with decanoic acid.

They wrote in the May 30, 2006, online issue of the Proceedings of the [U.S.] National Academy of Sciences that the transferase functioned as a cysteine/lysine dyad acyltransferase, in which two invariant residues (Lys-142 and Cys-176) functioned as acid/base catalysts.

"LipB is a very promising drug target,” explained senior author Dr. Matthias, head of the Hamburg European Molecular Biology Laboratory, "because it belongs to a vital pathway. Unlike other organisms M tuberculosis has no backup mechanism that could take over LipB's role. This means that an inhibitor blocking its active site would shut down key processes the bacterium needs to survive and replicate. This would be a very effective strategy for a drug.”



Related Links:
European Molecular Biology Laboratory
Max Planck Institute for Infection Biology