Global profiling and inhibition of protein lipidation in vector and host stages of the sleeping sickness parasite Trypanosoma brucei

Tate, EW; Wright, MH; Paape, D; Price, H; Smith, DF

Abstract

The enzyme N-myristoyltransferase (NMT) catalyzes the essential fatty acylation of substrate proteins with myristic acid in eukaryotes and is a validated drug target in the parasite Trypanosoma brucei, the causative agent of African trypanosomiasis (sleeping sickness). N-Myristoylation typically mediates membrane localization of proteins and is essential to the function of many. However, only a handful of proteins are experimentally validated as N-myristoylated in T. brucei. Here, we perform metabolic labeling with an alkyne-tagged myristic acid analogue, enabling the capture of lipidated proteins in insect and host life stages of T. brucei. We further compare this with a longer chain palmitate analogue to explore the chain length-specific incorporation of fatty acids into proteins. Finally, we combine the alkynyl-myristate analogue with NMT inhibitors and quantitative chemical proteomics to globally define N-myristoylated proteins in the clinically relevant bloodstream form parasites. This analysis reveals five ARF family small GTPases, calpain-like proteins, phosphatases, and many uncharacterized proteins as substrates of NMT in the parasite, providing a global view of the scope of this important protein modification and further evidence for the crucial and pleiotropic role of NMT in the cell.

Citation

Tate, E., Wright, M., Paape, D., Price, H., & Smith, D. (2016). Global profiling and inhibition of protein lipidation in vector and host stages of the sleeping sickness parasite Trypanosoma brucei. ACS Infectious Diseases, 2(6), 427-441. https://doi.org/10.1021/acsinfecdis.6b00034

• Journal Article Type: Article
• Acceptance Date: Apr 29, 2016
• Publication Date: Apr 29, 2016
• Journal: ACS Infectious Diseases
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 2
• Issue: 6
• Pages: 427-441
• DOI: https://doi.org/10.1021/acsinfecdis.6b00034
• Keywords: human African trypanosomiasis, N-myristoylation, chemical proteomics, click chemistry, protein lipidation, target validation
• Publisher URL: http://dx.doi.org/10.1021/acsinfecdis.6b00034