Quantitative relationship between sensitivity to beta-lactam antibiotics and beta-lactamase production in gram-negative bacteria--II. Non-steady-state treatment and progress curves.
Biochem Pharmacol
; 38(9): 1427-33, 1989 May 01.
Article
em En
| MEDLINE
| ID: mdl-2655602
ABSTRACT
A non-steady-state model is discussed for the study of the interplay between beta-lactamase activity and outer membrane permeability with slowly hydrolysed beta-lactams. The analysis shows (1) that the simple, steady-state model presented in the accompanying paper remains valid as long as kcat (i.e. k3 with chromosome-encoded class C beta-lactamases) is larger than 10(-3)/sec (generation time = 20 min or more); (2) that among the beta-lactam antibiotics studied here, the complete, non-steady-state model needs only be used in the case of aztreonam; (3) that the term "trapping" should be replaced by "formation of a covalent acyl-enzyme" and that such a phenomenon only contributes significantly to the resistance when penetration and hydrolysis are very slow and the periplasmic beta-lactamase concentration is very high. Aztreonam seems to be the only compound which fulfils the first two conditions.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Beta-Lactamases
/
Peptidil Transferases
/
Bactérias Gram-Negativas
/
Hexosiltransferases
/
Antibacterianos
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Revista:
Biochem Pharmacol
Ano de publicação:
1989
Tipo de documento:
Article
País de afiliação:
Bélgica