Functionally important amino acids in the Arabidopsis thylakoid phosphate transporter: homology modeling and site-directed mutagenesis.

ABSTRACT: The anion transporter 1 (ANTR1) from Arabidopsis thaliana, homologous to the mammalian members of the solute carrier 17 (SLC17) family, is located in the chloroplast thylakoid membrane. When expressed heterologously in Escherichia coli, ANTR1 mediates a Na(+)-dependent active transport of inorganic phosphate (P(i)). The aim of this study was to identify amino acid residues involved in P(i) binding and translocation by ANTR1 and in the Na(+) dependence of its activity. A three-dimensional structural model of ANTR1 was constructed using the crystal structure of glycerol 3-phosphate/phosphate antiporter from E. coli as a template. Based on this model and multiple sequence alignments, five highly conserved residues in plant ANTRs and mammalian SLC17 homologues have been selected for site-direc

SUBMITTER: Ruiz-Pavon L 

PROVIDER: S-EPMC2911078 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature