Polyphosphate and omptins: novel bacterial procoagulant agents

Area of Science:

• Microbiology
• Hematology
• Pathophysiology

Background:

• Severe sepsis often leads to multiple organ failure, with blood clotting system derangements playing a critical role.
• Microbial factors can significantly influence host hemostasis during infection.

Purpose of the Study:

• To review the roles of microbial polyphosphates and omptins in modulating the blood clotting system.
• To elucidate the mechanisms by which these microbial products affect hemostasis and contribute to disease pathogenesis.

Main Methods:

• Literature review of studies on polyphosphates and omptins in relation to blood clotting.
• Analysis of biochemical and genetic data on microbial modulation of coagulation factors and inhibitors.

Main Results:

• Polyphosphates enhance blood clotting by activating the contact pathway, accelerating factor V activation, and promoting resistant fibrin clots.
• Omptins, outer membrane proteases, inactivate tissue factor pathway inhibitor (TFPI), a key inhibitor of clot initiation.
• Yersinia pestis omptin (Pla) inactivates TFPI more rapidly than it activates plasminogen, suggesting a dual role in plague pathogenesis.

Conclusions:

• Microbial polyphosphates and omptins are significant modulators of hemostasis with implications for sepsis and infectious diseases.
• Omptin activity, particularly Pla in Yersinia pestis, may contribute to the unique pathology of plague through dual effects on clotting and fibrinolysis.