carbapenemase producing bacteria frequently possess resistance mechanisms to a wide-range of antibacterial agents, and are associated with high mortality and morbidity rates. some enzymes like extended-spectrum β-lactamase (esbl), new delhi metallo-beta-lactamase-1 (ndm-1), klebsiella pneumoniae carbapenemase (kpc), and oxa-producing enterobacteriaceae are very important in frequently isolated ...

Clinical use of beta-lactams has selected for beta-lactamase-producing organisms. Numerous beta-lactamases are known, and sequencing allows them to be divided into four Classes, A to D, with Classes A and C being the most important. Pharmaceutical chemists have responded to the spread of beta-lactamase-producing organisms by developing stable agents and inhibitors. Stability in penicillins and ...

An environmental isolate of Serratia fonticola resistant to carbapenems was shown to contain a genetic determinant encoding a metallo-beta-lactamase of the subclass B2. The Sfh-I enzyme exhibits some divergence from the previously characterized enzymes of this subclass. This is the first example of a naturally occurring metallo-beta-lactamase in Enterobacteriaceae.

Abstract Invited for the cover of this issue are Jesús Ferrando‐Soria, Donatella Armentano, Antonio Leyva‐Pérez, Emilio Pardo and co‐workers at University Valencia, Technical Valencia Calabria. The image depicts crystal structure a novel Zn II biological metal–organic framework that mimics β‐lactamase enzymes. Read full text article 10.1002/chem.202301325 .

background klebsiella pneumoniae is a family member of enterobacteriaceae. isolates of k. pneumoniae produce enzymes that cause decomposition of third generation cephalosporins. these enzymes are known as extended-spectrum beta-lactamase (esbl). resistance of k. pneumoniae to beta-lactamase antibiotics is commonly mediated by beta-lactamase genes. objectives the aim of this study was to identif...

The complete amino acid sequence of the p453-plasmid-mediated PIT-2 ,-lactamase (SHV1) was determined. The protein contains 265 residues. Peptides resulting from digestions with trypsin, Staphylococcus aureus V8 proteinase, chymotrypsin and Lys-C proteinase and cleavage with CNBr were separated and purified by using reverse-phase h.p.l.c. The amino acid sequence of each peptide was manually det...

Among a group of 116 clinically significant isolates of Bacteroides spp., 24 exhibited beta-lactamase activity greater than the basal level characteristic of most Bacteroides strains. Investigation of specific enzyme activity, iso-electric point and enzyme inhibition profiles revealed that the beta-lactamases involved could be divided into four groups, some showing similarity to those described...

About 70% of all Enterobacter cloacae strains tested possessed one of two species-specific beta-lactamases. These enzymes, E. cloacae beta-lactamase A and E. cloacae beta-lactamase B, with isoelectric points of 8.8 and 7.8, respectively, had the same pH and temperature optima. Both showed similar enzyme kinetics and were inhibited by cloxacillin but not by p-chloromercuribenzoate. E. cloacae be...