Purpose of review Polyphosphate (polyP) is an inorganic polymer that has

Purpose of review Polyphosphate (polyP) is an inorganic polymer that has recently been shown to be secreted by activated platelets. is also potentially a drug target as its contributions to hemostasis appear to be to accelerate blood clotting but are not required for blood clotting to happen. [Informative review of the many new roles that have been discovered for polyP with an emphasis to pathogens and the host response to them.] 5 Docampo R Moreno SN. Acidocalcisomes. Cell Calcium. 2011;50:113-119. [PMC free article] [PubMed] 6 Pisoni RL Lindley ER. Incorporation SP-II of [32P]orthophosphate into long chains of inorganic polyphosphate within lysosomes of human fibroblasts. J Biol Chem. 1992;267:3626-3631. [PubMed] 7 Ruiz FA Lea CR Oldfield E Docampo R. Human platelet dense granules contain polyphosphate and are similar to acidocalcisomes of bacteria and unicellular eukaryotes. J Biol Chem. 2004;279:44250-44257. [PubMed] 8 Kumble KD Kornberg A. Inorganic polyphosphate in mammalian cells and tissues. J Biol Chem. 1995;270:5818-5822. [PubMed] 9 Han KY Hong BS Yoon YJ et al. Polyphosphate blocks tumour metastasis via anti-angiogenic activity. Biochem J. 2007;406:49-55. [PMC free article] [PubMed] 10 Hernandez-Ruiz L Gonzalez-Garcia I Castro C et al. Inorganic polyphosphate and specific induction of apoptosis in human plasma cells. Haematologica. 2006;91:1180-1186. [PubMed] 11 Wang L Fraley CD Faridi J et al. Inorganic polyphosphate stimulates mammalian TOR a kinase involved in the proliferation of mammary cancer cells. Proc Natl Acad Sci U S A. 2003;100:11249-11254. [PMC free article] [PubMed] 12 Pavlov E Aschar-Sobbi R Campanella M et al. Inorganic polyphosphate and energy metabolism in mammalian cells. J Biol Chem. 2010;285:9420-9428. [PMC free article] [PubMed] 13 Kawazoe Y Shiba T Nakamura R et al. Induction of calcification in MC3T3-E1 cells by inorganic polyphosphate. J Dent Res. 2004;83:613-618. [PubMed] 14 Schr?der HC Kurz L Müller WE Lorenz B. Polyphosphate in bone. Biochemistry (Mosc) 2000;65:296-303. [PubMed] 15 Leyhausen G Lorenz B Zhu H et al. Inorganic polyphosphate in human osteoblast-like cells. J Bone Miner Res. 1998;13:803-812. [PubMed] 16 Galasso A Zollo M. The Nm23-H1-h-Prune complex in cellular physiology: a ‘tip of the iceberg’ protein network perspective. Mol Cell Biochem. 2009;329:149-159. [PubMed] 17 Tammenkoski M IKK-16 Koivula K Cusanelli E et al. Human metastasis regulator protein H-prune is a short-chain exopolyphosphatase. Biochemistry. 2008;47:9707-9713. [PubMed] 18 Smith SA Mutch NJ Baskar D et al. Polyphosphate modulates blood coagulation and fibrinolysis. Proc Natl Acad Sci U S A. 2006;103:903-908. [PMC free article] [PubMed] 19 Smith SA Morrissey JH. Polyphosphate as a general procoagulant agent. J Thromb Haemost. 2008;6:1750-1756. [PMC free article] [PubMed] 20 Smith SA Morrissey JH. Polyphosphate IKK-16 enhances fibrin clot structure. Blood. 2008;112:2810-2816. [PMC free article] [PubMed] IKK-16 21 Muller F Mutch NJ Schenk WA et al. Platelet polyphosphates are proinflammatory and procoagulant mediators in vivo. Cell. 2009;139:1143-1156. [PMC free article] [PubMed] 22 Mutch NJ Myles T Leung LLK Morrissey JH. Polyphosphate binds with high affinity to exosite II of thrombin. J Thromb Haemost. 2010;8:548-555. [PMC free article] [PubMed] 23 Smith SA Choi SH Davis-Harrison R et al. Polyphosphate exerts differential effects on blood clotting depending on polymer size. Blood. 2010;116:4353-4359. [PMC free article] [PubMed] 24 Semeraro F Ammollo CT Morrissey JH et al. Extracellular histones promote thrombin generation through platelet-dependent mechanisms: involvement of platelet TLR2 and TLR4. Blood. 2011;118:1952-1961. [PMC free article] [PubMed] 25 Choi SH Smith SA Morrissey JH. Polyphosphate is a cofactor for the activation of factor XI by thrombin. Blood. 2011;118:6963-6970. [PMC free article] [PubMed] IKK-16 26 Mutch NJ Engel R Uitte de Willige S et al. Polyphosphate modifies the fibrin network and down-regulates fibrinolysis by attenuating binding of tPA and plasminogen to fibrin. Blood. 2010;115:3980-3988. [PubMed] 27 Fukami MH Dangelmaier CA Bauer JS Holmsen H. Secretion subcellular localization and metabolic status of inorganic pyrophosphate in human platelets. A major constituent of the amine-storing granules. Biochem J. 1980;192:99-105. [PMC free article] IKK-16 [PubMed] 28 Dean GE Fishkes H Nelson PJ Rudnick G. The hydrogen ion-pumping adenosine triphosphatase of platelet dense granule membrane. Differences IKK-16 from F1F0- and phosphoenzyme-type.