title: Haemozoin (beta-haematin) biomineralization occurs by self-assembly near the lipid/water interface.
abstract: Several blood-feeding organisms, including the malaria parasite detoxify haem released from host haemoglobin by conversion to the insoluble crystalline ferriprotoporphyrin IX dimer known as haemozoin. To date the mechanism of haemozoin formation has remained unknown, although lipids or proteins have been suggested to catalyse its formation. We have found that beta-haematin (synthetic haemozoin) forms rapidly under physiologically realistic conditions near octanol/water, pentanol/water and lipid/water interfaces. Molecular dynamics simulations show that a precursor of the haemozoin dimer forms spontaneously in the absence of the competing hydrogen bonds of water, demonstrating that this substance probably self-assembles near a lipid/water interface in vivo.
authors.affiliation: Department of Chemistry, University of Cape Town, Private Bag, Rondebosch 7701, South Africa. tegan@science.uct.ac.za
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Egan
authors.forename: Jeff Y-J
authors.initials: JY
authors.lastname: Chen
authors.forename: Katherine A
authors.initials: KA
authors.lastname: de Villiers
authors.forename: Tebogo E
authors.initials: TE
authors.lastname: Mabotha
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Naidoo
authors.forename: Kanyile K
authors.initials: KK
authors.lastname: Ncokazi
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Langford
authors.forename: Don
authors.initials: D
authors.lastname: McNaughton
authors.forename: Shveta
authors.initials: S
authors.lastname: Pandiancherri
authors.forename: Bayden R
authors.initials: BR
authors.lastname: Wood
mesh_terms: D000818:Animals; D006420:Hemeproteins / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism* / Q000648:ultrastructure; D007700:Kinetics; D008055:Lipids / Q000737:chemistry*; D008958:Models, Molecular; D010963:Plasmodium falciparum / Q000737:chemistry; D013055:Spectrophotometry, Infrared; D013059:Spectrum Analysis, Raman; D014867:Water / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D006420:Hemeproteins; D008055:Lipids; D014867:Water; C020753:hemozoin