In a paper to be published in the Proceedings of the National Academy of Sciences, researchers from the University of Illinois at Urbana-Champaign and the University of Georgia report that a linear polymer known as polyphosphate speeds blood clotting and helps clots last longer. The paper appears online this week (Jan. 9-14) on the PNAS Web site.
Polyphosphate was shown to have three important roles, said James H. Morrissey, a biochemist in the U. of I. College of Medicine at Urbana-Champaign. The inorganic compound accelerates two parts of the coagulation cascade -- the contact-activation pathway and factor V, a protein that forms thrombin -- leading to fibrin and clots. Finally, he said, polyphosphate delays the breakdown of clots, which causes renewed bleeding.
"The net effect is accelerating the rate at which blood clots form and then prolonging how long they last," Morrissey said.
The successful research already has landed the U. of I. a three-year, $300,000 grant from the Roy J. Carver Charitable Trust to establish the Center for Hemostasis Research. The grant, which began Nov. 1, involves three U. of I. labs with Morrissey in the lead.
The PNAS report comes about a year after former Illinois scientist Roberto Docampo, now a professor of cellular biology at Georgia's Center for Tropical and Emerging Global Diseases, documented in the Journal of Biological Chemistry (Oct. 22, 2004) that dense granules in human platelets contain polyphosphate.
In the early 1990s, Docampo determined that a tiny granule, a subcellular pouch, in yeast, fungi and bacteria -- long thought to be for storage -- was a fully operational organelle. It contained pyrophosphatase, a pump-like enzyme that allows proton tran
Source:University of Illinois at Urbana-Champaign