TY - JOUR
T1 - Interaction of bacteroides fragilis and bacteroides thetaiotaomicron with the kallikrein-kinin system
AU - Murphy, Elizabeth C.
AU - Mörgelin, Matthias
AU - Cooney, Jakki C.
AU - Frick, Inga Maria
PY - 2011/7
Y1 - 2011/7
N2 - Many bacterial pathogens interfere with the contact system (kallikrein-kinin system) in human plasma. Activation of this system has two consequences: cleavage of high-molecular-mass kininogen (HK) resulting in release of the potent proinflammatory peptide bradykinin, and initiation of the intrinsic pathway of coagulation. In this study, two species of the Gram-negative anaerobic commensal organism Bacteroides, namely Bacteroides fragilis and Bacteroides thetaiotaomicron, were found to bind HK and fibrinogen, the major clotting protein, from human plasma as shown by immunoelectron microscopy and Western blot analysis. In addition, these Bacteroides species were capable of activating the contact system at its surface leading to a significant prolongation of the intrinsic coagulation time and also to the release of bradykinin. Members of the genus Bacteroides have been known to act as opportunistic pathogens outside the gut, with B. fragilis being the most common isolate from clinical infections, such as intra-abdominal abscesses and bacteraemia. The present results thus provide more insight into how Bacteroides species cause infection.
AB - Many bacterial pathogens interfere with the contact system (kallikrein-kinin system) in human plasma. Activation of this system has two consequences: cleavage of high-molecular-mass kininogen (HK) resulting in release of the potent proinflammatory peptide bradykinin, and initiation of the intrinsic pathway of coagulation. In this study, two species of the Gram-negative anaerobic commensal organism Bacteroides, namely Bacteroides fragilis and Bacteroides thetaiotaomicron, were found to bind HK and fibrinogen, the major clotting protein, from human plasma as shown by immunoelectron microscopy and Western blot analysis. In addition, these Bacteroides species were capable of activating the contact system at its surface leading to a significant prolongation of the intrinsic coagulation time and also to the release of bradykinin. Members of the genus Bacteroides have been known to act as opportunistic pathogens outside the gut, with B. fragilis being the most common isolate from clinical infections, such as intra-abdominal abscesses and bacteraemia. The present results thus provide more insight into how Bacteroides species cause infection.
UR - http://www.scopus.com/inward/record.url?scp=79959993374&partnerID=8YFLogxK
U2 - 10.1099/mic.0.046862-0
DO - 10.1099/mic.0.046862-0
M3 - Article
C2 - 21527472
AN - SCOPUS:79959993374
SN - 1350-0872
VL - 157
SP - 2094
EP - 2105
JO - Microbiology
JF - Microbiology
IS - 7
ER -