Production of a metallo-beta-lactamase activity was detected in a carbapenem-resistant Pseudomonas aeruginosa clinical isolate (isolate VR-143/97) from an Italian inpatient at the Verona University Hospital (northern Italy). The metallo-beta-lactamase determinant was isolated from a genomic library of VR-143/97, constructed in an Escherichia coli plasmid vector, by screening for clones with red...

Penicillin-binding proteins (PBPs) are involved in the regulation of beta-lactamase expression by determining the level of anhydromuramylpeptides in the periplasmatic space. It was hypothesized that one or more PBPs act as a sensor in the beta-lactamase induction pathway. We have performed induction studies with Escherichia coli mutants lacking one to four PBPs with DD-carboxypeptidase activity...

In this study, it was aimed to investigate the presence of Klebsiella pneumoniae and phenotypically carbapenemase, extended-spectrum β-lactamase (ESBL), acquired-AmpC beta-lactamase, multiple antibiotic resistance isolates in faeces budgerigars parrots. A total 96 faecal samples belonging 54 42 parrots were used study. Cultivation performed on various media for identification pneuomiae from col...

Antibiotic resistance genes (ARGs) pose a widespread concern for human health and wastewater treatment plants (WWTPs) are considered to be major source of ARG transmission. In this paper, the potential hosts genetic characteristics ARGs in influent, activated sludge effluent WWTPs Xinjiang were studied by metagenomics. Bacitracin gene (bacA), beta-lactamase (class A beta-lactamase), multidrug (...

Urinary tract infections (UTIs) are among the most common diagnosed in clinical practice. Treatment is often initiated before microbiological confirmation and anti-microbial susceptibility testing. With rapidly rising antibiotic resistance treatment failures not uncommon. Beta-lactamase production by gram-negative bacteria causing UTI commonest mode of drug resistance. The aim current study was...

Using an isogenic system, we have determined the impact that the four promoters known to control bla(TEM) gene expression have on beta-lactamase activity. For both TEM-1 and TEM-30, this activity gradually increased in relation to the presence of promoters P3, Pa/Pb, and P4 upstream of the corresponding gene. Promoter P5, only found upstream of the bla(TEM-1B) gene, was related to the highest e...

We isolated five clinical strains (three Proteus mirabilis and two Klebsiella pneumoniae) with beta-lactam resistance phenotypes consistent with production of an AmpC-type beta-lactamase. The predicted amino acid sequences of the enzymes were typical of class C beta-lactamases. The enzymes were identified as CMY-2, CMY-4 and a new CMY-variant beta-lactamase, CMY-12. The AmpC beta-lactamases fro...

Pseudomonas aeruginosa is an opportunistic pathogen which is naturally resistant to a large range of antibiotics like lots of Beta–Lactams (penicillins, cephalosporins and carbapenems) and may cause additional resistance after unsuccessful treatment. The understanding of beta-lactamase identification and detection in these bacteria is very valuable. In recent years a number of variety of new be...

We investigated a Klebsiella oxytoca isolate demonstrating resistance to imipenem, meropenem, extended-spectrum cephalosporins, and aztreonam. The MICs of both imipenem and meropenem were 32 microg/ml. The beta-lactamase activity against imipenem and meropenem was inhibited in the presence of clavulanic acid. Isoelectric focusing studies demonstrated five beta-lactamases with pIs of 8.2 (SHV-46...