Hothorn M, et al. (2009) Catalytic core of a membrane-associated eukaryotic polyphosphate polymerase. Science 324(5926):513-6
Abstract: Polyphosphate (polyP) occurs ubiquitously in cells, but its functions are poorly understood and its synthesis has only been characterized in bacteria. Using x-ray crystallography, we identified a eukaryotic polyphosphate polymerase within the membrane-integral vacuolar transporter chaperone (VTC) complex. A 2.6 angstrom crystal structure of the catalytic domain grown in the presence of adenosine triphosphate (ATP) reveals polyP winding through a tunnel-shaped pocket. Nucleotide- and phosphate-bound structures suggest that the enzyme functions by metal-assisted cleavage of the ATP gamma-phosphate, which is then in-line transferred to an acceptor phosphate to form polyP chains. Mutational analysis of the transmembrane domain indicates that VTC may integrate cytoplasmic polymer synthesis with polyP membrane translocation. Identification of the polyP-synthesizing enzyme opens the way to determine the functions of polyP in lower eukaryotes.
|Status: Published||Type: Journal Article | Research Support, Non-U.S. Gov't||PubMed ID: 19390046|
Topics addressed in this paper
Number of different genes curated to this paper: 5
- To go to the Locus page for a gene, click on the gene name.
|Fungal Related Genes/Proteins|
|Non-Fungal Related Genes/Proteins|
|Protein Physical Properties|
|Protein Sequence Features|
|Protein/Nucleic Acid Structure|