Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The adhesiveness of 2 unencapsulated nonfimbriated strains of Haemophilus influenzae, 23459 and 23330, and the encapsulated fimbriated strain 770235 to extracellular matrix (ECM) and to its isolated components was studied, as was the potential of H. influenzae plasminogen receptors to enhance degradation of ECM and bacterial penetration through basement membrane. All strains exhibited efficient adhesiveness to reconstituted basement membrane and to ECM from cultured human endothelial cells. Strains 23459 and 23330 efficiently adhered to immobilized laminin, fibronectin, and various collagens. Strain 770235 adhered efficiently to fibronectin and type I and III collagens and with low efficiency to laminin. With all 3 strains, plasmin generated on H. influenzae plasminogen receptors degraded laminin and fibronectin as well as ECM from human endothelial cells. Plasmin bound on H. influenzae cells also potentiated penetration of bacteria through a basement membrane preparation reconstituted on membrane filters. These results give evidence for a role of ECM adherence and plasminogen activation in the spread of H. influenzae through tissue barriers.
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PMID:Interaction of Haemophilus influenzae with the mammalian extracellular matrix. 862 65

The adherence of clinical isolates of nonencapsulated Haemophilus influenzae strains from patients with chronic bronchitis to distinct immobilized extracellular matrix components was determined. With selected strains the induction of plasmin formation by these isolates was studied. The strains could be divided into two groups: strains that showed a very high level of adherence to laminin and type I collagen, as well as adhesion to fibronectin and strains that showed only a moderate level of adhesion to laminin and a low level of adhesion to fibronectin. Plasmin formation was demonstrated for three out of eight isolates. Persisting and nonpersisting strains did not differ quantitatively or qualitatively with respect to the level of adhesiveness to the distinct matrix proteins and in their ability to induce plasmin formation.
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PMID:Interaction of clinical isolates of nonencapsulated Haemophilus influenzae with mammalian extracellular matrix proteins. 1079 2

Invasive bacterial pathogens intervene at various stages and by various mechanisms with the mammalian plasminogen/plasmin system. A vast number of pathogens express plasmin(ogen) receptors that immobilize plasmin(ogen) on the bacterial surface, an event that enhances activation of plasminogen by mammalian plasminogen activators. Bacteria also influence secretion of plasminogen activators and their inhibitors from mammalian cells. The prokaryotic plasminogen activators streptokinase and staphylokinase form a complex with plasmin(ogen) and thus enhance plasminogen activation. The Pla surface protease of Yersinia pestis resembles mammalian activators in function and converts plasminogen to plasmin by limited proteolysis. In essence, plasminogen receptors and activators turn bacteria into proteolytic organisms using a host-derived system. In Gram-negative bacteria, the filamentous surface appendages fimbriae and flagella form a major group of plasminogen receptors. In Gram-positive bacteria, surface-bound enzyme molecules as well as M-protein-related structures have been identified as plasminogen receptors, the former receptor type also occurs on mammalian cells. Plasmin is a broad-spectrum serine protease that degrades fibrin and noncollagenous proteins of extracellular matrices and activates latent procollagenases. Consequently, plasmin generated on or activated by Haemophilus influenzae, Salmonella typhimurium, Streptococcus pneumoniae, Y. pestis, and Borrelia burgdorferi has been shown to degrade mammalian extracellular matrices. In a few instances plasminogen activation has been shown to enhance bacterial metastasis in vitro through reconstituted basement membrane or epithelial cell monolayers. In vivo evidence for a role of plasminogen activation in pathogenesis is limited to Y. pestis, Borrelia, and group A streptococci. Bacterial proteases may also directly activate latent procollagenases or inactivate protease inhibitors of human plasma, and thus contribute to tissue damage and bacterial spread across tissue barriers.
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PMID:Bacterial plasminogen activators and receptors. 1174 90