title: Aspartic proteases from Plasmodium chabaudi: a rodent model for human malaria.
abstract: Intraerythrocytic malaria parasites degrade haemoglobin to provide nutrients for their own growth and maturation. Plasmodium aspartic proteases known as plasmepsins play an important role on haemoglobin degradation and are being studied as drug targets for chemotherapy of malaria. The rodent model for human malaria, Plasmodium chabaudi, is an experimentally good model for therapy drug design. The gene encoding an aspartic protease precursor (proplasmepsin) from the rodent malaria parasite P. chabaudi was cloned and sequenced. A theoretical 3D structure model was constructed by comparative homology and used for superimposition with other known models. Analysis of the P. chabaudi and Plasmodium yoelli genomes revealed in both the presence of at least seven plasmepsins and each one has sequence similarity to its plasmepsin counterpart of the human malaria Plasmodium falciparum. The predicted proteins were confirmed as plasmepsins by detection on Blocks Database of three characteristic blocks of the eukaryotic and viral aspartic protease family. Analysis of the proline-rich loop amino acid sequence of these plasmepsins suggests that they constitute characteristic motifs of each plasmepsin group suggesting that these sequence variations are related with different substrate specificities.
authors.affiliation: Departamento de Biotecnologia, Instituto Nacional de Engenharia e Tecnologia Industrial, UTPAM, Edifício F, Estrada do Paço do Lumiar, 1649-038 Lisboa, Portugal.
authors.forename: Tiago M
authors.initials: TM
authors.lastname: Martins
authors.forename: Carlos
authors.initials: C
authors.lastname: Novo
authors.forename: Virgílio E
authors.initials: VE
authors.lastname: do Rosário
authors.forename: Ana
authors.initials: A
authors.lastname: Domingos
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000235:genetics*; D016678:Genome; D006801:Humans; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016788:Plasmodium chabaudi / Q000201:enzymology / Q000235:genetics*; D016133:Polymerase Chain Reaction
chemical_list: D016282:Aspartic Acid Endopeptidases