Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University,Parkville, Victoria, Australia.
J Infect Dis. 2017 May 1;215(9):1435-1444. doi: 10.1093/infdis/jix156.
The emergence of artemisinin resistance in the malaria parasite Plasmodium falciparum poses a major threat to the control and elimination of malaria. Certain point mutations in the propeller domain of PfKelch13 are associated with resistance, but PfKelch13 mutations do not always result in clinical resistance. The underlying mechanisms associated with artemisinin resistance are poorly understood, and the impact of PfKelch13 mutations on cellular biochemistry is not defined.
This study aimed to identify global biochemical differences between PfKelch13-mutant artemisinin-resistant and -sensitive strains of P. falciparum by combining liquid chromatography-mass spectrometry (LC-MS)-based proteomics, peptidomics, and metabolomics.
Proteomics analysis found both PfKelch13 mutations examined to be specifically associated with decreased abundance of PfKelch13 protein. Metabolomics analysis demonstrated accumulation of glutathione and its precursor, gamma-glutamylcysteine, and significant depletion of 1 other putative metabolite in resistant strains. Peptidomics analysis revealed lower abundance of several endogenous peptides derived from hemoglobin (HBα and HBβ) in the artemisinin-resistant strains.
PfKelch13 mutations associated with artemisinin resistance lead to decreased abundance of PfKelch13 protein, decreased hemoglobin digestion, and enhanced glutathione production.
疟原虫青蒿素耐药性的出现对疟疾的控制和消除构成了重大威胁。PfKelch13 螺旋桨结构域的某些点突变与耐药性相关，但 PfKelch13 突变并不总是导致临床耐药性。与青蒿素耐药性相关的潜在机制尚未得到充分理解，PfKelch13 突变对细胞生物化学的影响也尚未确定。
本研究旨在通过结合基于液相色谱-质谱（LC-MS）的蛋白质组学、肽组学和代谢组学，鉴定 PfKelch13 突变的青蒿素耐药和敏感疟原虫株之间的全球生化差异。
蛋白质组学分析发现，两种被检测的 PfKelch13 突变均与 PfKelch13 蛋白丰度降低特异性相关。代谢组学分析表明，耐药株中谷胱甘肽及其前体γ-谷氨酰半胱氨酸积累，另一种假定代谢物显著减少。肽组学分析显示，青蒿素耐药株中来源于血红蛋白（HBα 和 HBβ）的几种内源性肽的丰度降低。
与青蒿素耐药性相关的 PfKelch13 突变导致 PfKelch13 蛋白丰度降低、血红蛋白消化减少和谷胱甘肽生成增强。
