3f9q
Re-refinement of uncomplexed plasmepsin II from Plasmodium falciparum.Re-refinement of uncomplexed plasmepsin II from Plasmodium falciparum.
Structural highlights
FunctionPLM2_PLAFX During the asexual blood stage, participates in initial cleavage of native host hemoglobin (Hb) resulting in Hb denaturation (PubMed:11782538, PubMed:15574427, PubMed:8844673). May cleave preferentially denatured hemoglobin that has been cleaved by PMI (PubMed:8844673). Digestion of host Hb is an essential step which provides the parasite with amino acids for protein synthesis, and regulates osmolarity (Probable).[1] [2] [3] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe carboxylate atoms of the two catalytic aspartic acid residues in aspartic proteases are nearly coplanar and in the uncomplexed form share an in-plane nucleophilic water molecule that is central to the mechanism of these enzymes. This note reports that while reviewing the electron-density maps derived from the deposited data for uncomplexed plasmepsin II from Plasmodium falciparum [Asojo et al. (2003), J. Mol. Biol. 327, 173-181; PDB code 1lf4], it was discovered that the aspartic acid residues in this structure should in fact be distinctly noncoplanar. The crystallographic model from the deposited coordinates has been re-refined against the 1.9 A resolution published diffraction data to an R(cryst) of 21.2% and an R(free) of 22.2%. The catalytic water molecule is present, but the plane of the carboxylate group of Asp214 is rotated by 66 degrees from its original position. Crystallographic evidence for noncoplanar catalytic aspartic acids in plasmepsin II resides in the Protein Data Bank.,Robbins AH, Dunn BM, Agbandje-McKenna M, McKenna R Acta Crystallogr D Biol Crystallogr. 2009 Mar;65(Pt 3):294-6. Epub 2009, Feb 20. PMID:19237752[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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