| Registro completo |
| Provedor de dados: |
BJMBR
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| País: |
Brazil
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| Título: |
A study of the interaction between Helicobacter pylori and components of the human fibrinolytic system
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| Autores: |
Yarzábal,A.
Avilán,L.
Hoelzl,K.
Muñoz,M. de
Puig,J.
Kansau,I.
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| Data: |
2000-09-01
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| Ano: |
2000
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| Palavras-chave: |
Helicobacter pylori
Plasminogen
T-PA
Urokinase
Plasminogen activation
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| Resumo: |
The interaction of plasminogen, tissue plasminogen activator (t-PA) and urokinase with a clinical strain of Helicobacter pylori was studied. Plasminogen bound to the surface of H. pylori cells in a concentration-dependent manner and could be activated to the enzymatic form, plasmin, by t-PA. Affinity chromatography assays revealed a plasminogen-binding protein of 58.9 kDa in water extracts of surface proteins. Surface-associated plasmin activity, detected with the chromogenic substrate CBS 00.65, was observed only when plasminogen and an exogenous activator were added to the cell suspension. The two physiologic plasminogen activators, t-PA and urokinase, were also shown to bind to and remain active on the surface of bacterial cells. epsilon-Aminocaproic acid caused partial inhibition of t-PA binding, suggesting that the kringle 2 structure of this activator is involved in the interaction with surface receptors. The activation of plasminogen by t-PA, but not urokinase, strongly depended on the presence of cells and a 25-fold enhancer effect on the initial velocity of activation by t-PA compared to urokinase was established. Furthermore, a relationship between cell concentration and the initial velocity of activation was demonstrated. These findings support the concept that plasminogen activation by t-PA on the bacterial surface is a surface-dependent reaction which offers catalytic advantages.
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| Tipo: |
Info:eu-repo/semantics/article
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| Idioma: |
Inglês
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| Identificador: |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2000000900004
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| Editor: |
Associação Brasileira de Divulgação Científica
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| Relação: |
10.1590/S0100-879X2000000900004
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| Formato: |
text/html
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| Fonte: |
Brazilian Journal of Medical and Biological Research v.33 n.9 2000
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| Direitos: |
info:eu-repo/semantics/openAccess
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