Leishmania Mexicana Potential Drug Target

We have been studying the Leishmania mexicana protein kinase Lmx‐MPK1. Lmx‐MPK1 is required for parasite viability in the host and represents a potential therapeutic target. We have been studying the interaction of the human p38 mitogen‐activated protein kinase (p38 MAPK) inhibitor, BIRB 796, with Lmx‐ MPK1. BIRB 796 is a unique allosteric MAPK inhibitor which binds to a highly conserved Asp‐Phe‐Gly motif within the active site of p38 MAPK. This site is conserved in other MAPKs and Lmx‐MPK1 as well. In order to assess BIRB 796 binding to LmxMPK1, we used fluorescence quenching to determine structural changes resulting from the binding event by measuring a change in tryptophan signaling at 290nm excitation and 340nm emission wavelengths. We will report on our results applying this technology to characterize kinase inhibitor binding.