title: Activation of blood clotting factors by microbial proteinases.
abstract: There are very few reports on the involvement of bacterial proteinases on the blood clotting system using both human plasma and purified clotting factors. We studied whether microbial proteinases from the opportunistic pathogens Candida albicans, Pseudomonas aeruginosa and Serratia marcescens activate the blood clotting cascade by using normal human plasma, human plasmas deficient in clotting factor XII or X, and also by using purified clotting factors XII, X and prothrombin. All proteinases tested activated either clotting factor XII or prothrombin in vitro, thus resulting in generation of thrombin. Clotting factor X was converted to the active form (Xa) by both Candida and Pseudomonas proteinases, but not by Serratia proteinase. These results suggest that peripheral and systemic blood circulation may be impaired by activation of the blood clotting cascade by microbial infections, especially in septic patients, which would enhance disseminated intravascular coagulation and multi-organ failure.
authors.affiliation: Department of Oral Microbiology, Fukuoka Dental College, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kaminishi
authors.forename: H
authors.initials: H
authors.lastname: Hamatake
authors.forename: T
authors.initials: T
authors.lastname: Cho
authors.forename: T
authors.initials: T
authors.lastname: Tamaki
authors.forename: N
authors.initials: N
authors.lastname: Suenaga
authors.forename: T
authors.initials: T
authors.lastname: Fujii
authors.forename: Y
authors.initials: Y
authors.lastname: Hagihara
authors.forename: H
authors.initials: H
authors.lastname: Maeda
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects* / Q000502:physiology; D002176:Candida albicans / Q000201:enzymology*; D002417:Cattle; D010450:Endopeptidases / Q000378:metabolism / Q000494:pharmacology*; D005170:Factor X / Q000378:metabolism; D005174:Factor XII / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry; D009894:Opportunistic Infections / Q000097:blood; D011516:Prothrombin / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000201:enzymology*; D018805:Sepsis / Q000097:blood; D012706:Serratia marcescens / Q000201:enzymology; D013379:Substrate Specificity
chemical_list: D009842:Oligopeptides; D011516:Prothrombin; D005170:Factor X; D005174:Factor XII; D010450:Endopeptidases