Variant of Penicillinase Mediated by an R Factor in Escherichia coli
Tetsuo Sawai,Tetsuo Sawai,Katsutoshi Takahashi,Katsutoshi Takahashi,Saburo Yamagishi,Saburo Yamagishi,Susumu Mitsuhashi,Susumu Mitsuhashi +7 more
Reads0
Chats0
TLDR
Comparisons were observed between the enzyme and the type I penicillinase at optimal pH, optimal temperature, substrate specificity, Michaelis constants for penicillins and cephaloridine, and effect of inhibitors, and antiserum against type I Penicillinases showed cross-reaction against this enzyme.Abstract:
The penicillinase from an Escherichia coli strain harboring an R factor R(GN823) was purified and its properties were compared with those of a known type I penicillinase mediated by R factors. The molecular weight and S(20,w) of the enzyme were 22,600 and 2.42S, respectively. The isoelectric point of the enzyme was 6.9. These values are clearly different from those of type I penicillinase. The specific activity of the enzyme was 84,700 units per mg of the purified enzyme protein, which is about 20 times higher than that of the type I penicillinase. However, similarities were observed between the enzyme and the type I-penicillinase at optimal pH (6.5 to 7.0), optimal temperature (40 to 45C), substrate specificity, Michaelis constants for penicillins and cephaloridine, and effect of inhibitors. Furthermore, antiserum against type I penicillinase showed cross-reaction against this enzyme. The enzyme was named type Ib penicillinase, and the original type I penicillinase was renamed type Ia-penicillinase.read more
Citations
More filters
Book ChapterDOI
The β-Lactamases of Gram-Negative Bacteria and their Possible Physiological Role
M H Richmond,Richard B. Sykes +1 more
TL;DR: There is complexity in breakdown of the cephalosporins after β -lactamase action as there is no sporin and the formation of any single product—a fact that invalidates the iodometric assay of cep Halosporinase for absolute measurement.
Journal ArticleDOI
Uniform nomenclature for bacterial plasmids: a proposal.
TL;DR: This work aims to demonstrate the efforts towards in-situ applicability of EMMARM, which aims to provide real-time information about the phytochemical properties of E. coli.
Journal ArticleDOI
Analytical isoelectric focusing of R factor-determined beta-lactamases: correlation with plasmid compatibility.
M Matthew,R W Hedges +1 more
TL;DR: The TEM-type beta-lactamases are promiscuously distributed among plasmids of a wide variety of compatibility groups, whereas the various oxacillin-hydrolyzing enzymes show some degree of correlation with compatibility.
Journal ArticleDOI
Outer membrane permeation of beta-lactam antibiotics in Escherichia coli, Proteus mirabilis, and Enterobacter cloacae.
TL;DR: The results suggested that the main pathway for cephalosporin permeation is the pore made up of these proteins, and it was suggested that ampicillin and other penicillins possess another unknown route for outer membrane permeation.
Journal ArticleDOI
Transmissible multiple drug resistance in Enterobacteriaceae.
Julian Davies,R. Rownd +1 more
References
More filters
Journal Article
Protein Measurement with the Folin Phenol Reagent
TL;DR: Procedures are described for measuring protein in solution or after precipitation with acids or other agents, and for the determination of as little as 0.2 gamma of protein.
Journal ArticleDOI
The Determination of Enzyme Dissociation Constants
Hans Lineweaver,Dean Burk +1 more
TL;DR: On the basis of the assumed theory the rate of the observed reaction is directly proportional to the concentration of the enzyme-substrate compound, where (E:l = (ES).
Journal ArticleDOI
Estimation of the molecular weights of proteins by Sephadex gel-filtration.
TL;DR: The results are similar to those of previous studies, where the objective was to establish a cause-and-effect relationship, rather than a straightforward relationship between the number of cells and the content of the molecule.
Journal ArticleDOI
The release of enzymes from Escherichia coli by osmotic shock and during the formation of spheroplasts.
Harold C. Neu,Leon A. Heppel +1 more
TL;DR: A new method for releasing most of the inducible alkaline phosphatases and of the cyclic phosphodiesterase in high yield without greatly impairing the viability of the cells is developed.