Substrate specificity of HMRZ-86 for beta-lactamases, including extended-spectrum beta-lactamases (ESBLs).
J Infect Chemother
; 13(6): 390-5, 2007 Dec.
Article
em En
| MEDLINE
| ID: mdl-18095087
ABSTRACT
HMRZ-86 was designed as a new chromogenic cephalosporin to detect extended-spectrum beta-lactamases (ESBLs) and similar evolved beta-lactamases, such as metallo-beta-lactamases, derepressed AmpC, and extended oxacillinase. We report here our investigation of the kinetic parameters of several types of beta-lactamases to show the enzymatic characteristics of HMRZ-86. The Michaelis constant (Km values of HMRZ-86 for ESBLs were twice to three and half times as high as those of nitrocefin, and the maximum velocity (Vmax) was one-fifth that of nitrocefin. The Km and Vmax of HMRZ-86 for AmpC were both smaller than those of nitrocefin. The kinetic parameters of HMRZ-86 for metallo beta-lactamase (MBL) were very variable, depending on the type of buffer solution used and the concentration of zinc ions. For MBL, the Km values of HMRZ-86 were higher than those of nitrocefin, but the Vmax values were almost the same as those of nitrocefin. Although the chemical structure of HMRZ-86 is similar to that of nitrocefin, we think the enzymatic reactivities of the two entities for beta-lactamases are very different.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Beta-Lactamases
/
Cefalosporinas
/
Antibacterianos
Limite:
Humans
Idioma:
En
Revista:
J Infect Chemother
Assunto da revista:
MICROBIOLOGIA
/
TERAPIA POR MEDICAMENTOS
Ano de publicação:
2007
Tipo de documento:
Article
País de afiliação:
Japão