3c02

Publication Abstract from PubMed

The 2.05-A resolution structure of the aquaglyceroporin from the malarial parasite Plasmodium falciparum (PfAQP), a protein important in the parasite's life cycle, has been solved. The structure provides key evidence for the basis of water versus glycerol selectivity in aquaporin family members. Unlike its closest homolog of known structure, GlpF, the channel conducts both glycerol and water at high rates, framing the question of what determines high water conductance in aquaporin channels. The universally conserved arginine in the selectivity filter is constrained by only two hydrogen bonds in GlpF, whereas there are three in all water-selective aquaporins and in PfAQP. The decreased cost of dehydrating the triply-satisfied arginine cation may provide the basis for high water conductance. The two Asn-Pro-Ala (NPA) regions of PfAQP, which bear rare substitutions to Asn-Leu-Ala (NLA) and Asn-Pro-Ser (NPS), participate in preserving the orientation of the selectivity filter asparagines in the center of the channel.

Crystal structure of the aquaglyceroporin PfAQP from the malarial parasite Plasmodium falciparum.,Newby ZE, O'Connell J 3rd, Robles-Colmenares Y, Khademi S, Miercke LJ, Stroud RM Nat Struct Mol Biol. 2008 Jun;15(6):619-25. Epub 2008 May 25. PMID:18500352^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.