title: Haem-activated promiscuous targeting of artemisinin in Plasmodium falciparum.
abstract: The mechanism of action of artemisinin and its derivatives, the most potent of the anti-malarial drugs, is not completely understood. Here we present an unbiased chemical proteomics analysis to directly explore this mechanism in Plasmodium falciparum. We use an alkyne-tagged artemisinin analogue coupled with biotin to identify 124 artemisinin covalent binding protein targets, many of which are involved in the essential biological processes of the parasite. Such a broad targeting spectrum disrupts the biochemical landscape of the parasite and causes its death. Furthermore, using alkyne-tagged artemisinin coupled with a fluorescent dye to monitor protein binding, we show that haem, rather than free ferrous iron, is predominantly responsible for artemisinin activation. The haem derives primarily from the parasite's haem biosynthesis pathway at the early ring stage and from haemoglobin digestion at the latter stages. Our results support a unifying model to explain the action and specificity of artemisinin in parasite killing.
authors.affiliation: Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore.|The State Key Laboratory of Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing 210023, China.|Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research &Technology (SMART), Singapore 138602, Singapore.|Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore.
authors.forename: Jigang
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117585, Singapore.
authors.forename: Chong-Jing
authors.initials: CJ
authors.lastname: Zhang
authors.affiliation: Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545, Singapore.
authors.forename: Wan Ni
authors.initials: WN
authors.lastname: Chia
authors.affiliation: Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545, Singapore.
authors.forename: Cheryl C Y
authors.initials: CC
authors.lastname: Loh
authors.affiliation: NUS Environmental Research Institute, Singapore 117411, Singapore.
authors.forename: Zhengjun
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore.
authors.forename: Yew Mun
authors.identifier: http://orcid.org/0000-0002-8360-7689
authors.initials: YM
authors.lastname: Lee
authors.affiliation: Department of Anaesthesiology, Singapore General Hospital, Singapore 169608, Singapore.
authors.forename: Yingke
authors.initials: Y
authors.lastname: He
authors.affiliation: School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China.
authors.forename: Li-Xia
authors.initials: LX
authors.lastname: Yuan
authors.affiliation: Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore.
authors.forename: Teck Kwang
authors.initials: TK
authors.lastname: Lim
authors.affiliation: Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research &Technology (SMART), Singapore 138602, Singapore.
authors.forename: Min
authors.initials: M
authors.lastname: Liu
authors.affiliation: NUS Environmental Research Institute, Singapore 117411, Singapore.
authors.forename: Chin Xia
authors.identifier: http://orcid.org/0000-0001-9620-2405
authors.initials: CX
authors.lastname: Liew
authors.affiliation: Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545, Singapore.
authors.forename: Yan Quan
authors.initials: YQ
authors.lastname: Lee
authors.affiliation: Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore.
authors.forename: Jianbin
authors.initials: J
authors.lastname: Zhang
authors.affiliation: College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Nianci
authors.initials: N
authors.lastname: Lu
authors.affiliation: Department of Biomedical Engineering, National University of Singapore, Singapore 117583, Singapore.|Department of Mechanical Engineering, National University of Singapore, Singapore 117575, Singapore.
authors.forename: Chwee Teck
authors.initials: CT
authors.lastname: Lim
authors.affiliation: The State Key Laboratory of Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing 210023, China.
authors.forename: Zi-Chun
authors.initials: ZC
authors.lastname: Hua
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117585, Singapore.
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
authors.affiliation: Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore.
authors.forename: Han-Ming
authors.initials: HM
authors.lastname: Shen
authors.affiliation: Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545, Singapore.
authors.forename: Kevin S W
authors.initials: KS
authors.lastname: Tan
authors.affiliation: Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore.|NUS Environmental Research Institute, Singapore 117411, Singapore.
authors.forename: Qingsong
authors.initials: Q
authors.lastname: Lin
mesh_terms: D000962:Antimalarials / Q000494:pharmacology*; D037621:Artemisinins / Q000737:chemistry / Q000494:pharmacology*; D002616:Chemical Engineering; D006418:Heme / Q000737:chemistry / Q000378:metabolism*; D008958:Models, Molecular; D015394:Molecular Structure; D010963:Plasmodium falciparum / Q000187:drug effects*; D011487:Protein Conformation; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D000962:Antimalarials; D037621:Artemisinins; D015800:Protozoan Proteins; D006418:Heme; C031327:artemisinin