Kinetic studies on inactivation of Citrobacter freundii cephalosporinase by sulbactam
نویسندگان
چکیده
منابع مشابه
Kinetic studies on inactivation of Citrobacter freundii cephalosporinase by sulbactam.
The inactivation kinetics for inhibition by sulbactam (CP45,899) of Citrobacter freundii GN346 cephalosporinase were studied in detail and compared with those of type Ib penicillinase or TEM-2 beta-lactamase mediated by R plasmid RGN823. The rate constant for progressive inactivation of the cephalosporinase was significantly larger than that measured with the penicillinase. The number of sulbac...
متن کاملCovalent binding of moxalactam to cephalosporinase of Citrobacter freundii.
The inhibition of Citrobacter freundii cephalosporinase activity by moxalactam is shown to be due to the formation of a transiently stable covalent complex, probably acyl enzyme. The covalent complex formed was identified by coelution of [14C] moxalactam with the enzyme by using Sephadex G-25 gel filtration in the presence of 5.7 M guanidine hydrochloride and by analytical isoelectric focusing....
متن کاملInteraction of cefpirome and a cephalosporinase from Citrobacter freundii GN7391.
The interaction of cefpirome and a cephalosporinase from Citrobacter freundii, including hydrolysis and inhibition, was studied in comparison with those of cefotiam, cefotaxime, and ceftazidime. Cefpirome was hydrolyzed by the enzyme more rapidly at Vmax than were cefotaxime and ceftazidime. However, the low affinity of the enzyme for cefpirome caused a reduction in the hydrolytic rate of cefpi...
متن کاملDelayed inactivation of Citrobacter freundii cephalosporinase by 6 beta-[3-(2-chlorophenyl)-5-methyl-4-isoxazolyl]penicillin sulfone.
When Citrobacter freundii cephalosporinase was incubated with 6 beta-[3-(2-chlorophenyl)-5-methyl-4-isoxazolyl]penicillin sulfone (cloxacillin sulfone) in phosphate buffer, the enzyme was suddenly inactivated just after the completion of enzymatic degradation of the cloxacillin sulfone. Such delayed inactivation was due to a secondary inhibitor formed from cloxacillin sulfone during the incubat...
متن کاملGenetic Characterization of Atypical Citrobacter freundii
The ability of a bacterial population to survive in different niches, as well as in stressful and rapidly changing environmental conditions, depends greatly on its genetic content. To survive such fluctuating conditions, bacteria have evolved different mechanisms to modulate phenotypic variations and related strategies to produce high levels of genetic diversity. Laboratories working in microbi...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Antimicrobial Agents and Chemotherapy
سال: 1983
ISSN: 0066-4804,1098-6596
DOI: 10.1128/aac.24.1.23