This study was designed to evaluate the performance of the broth microdilution (BMD) test in detecting the production of Klebsiella pneumoniae carbapenemases (KPCs) and metallo-β-lactamases (MBLs) in clinical isolates of gram-negative bacilli by using various β-lactamase inhibitors. A carbapenemase detection test, comprised of Mueller-Hinton broth containing serial twofold dilutions of imipenem...

Specific boronic acids are generally powerful tetrahedral intermediate/transition state analogue inhibitors of serine amidohydrolases. This group of enzymes includes bacterial β-lactamases and DD-peptidases where there has been considerable development of boronic acid inhibitors. This paper describes the synthesis, determination of the inhibitory activity, and analysis of the results from two α...

We studied the prevalence of ceftazidime resistance in Pseudomonas aeruginosa and the rates of extended-spectrum β-lactamase (ESBL), AmpC β-lactamase (AmpC) and metallo-β-lactamase (MBL) production among the ceftazidime resistant Pseudomonas aeruginosa. A very high rate of MBL production was observed, which suggested it to be an important contributing factor for ceftazidime resistance among Pse...

INTRODUCTION This study analyzed the relationship between the ISEcp1 element and bla(CTX-M) genes of Escherichia coli isolates that produce extended-spectrum β-lactamase (ESBL) in community settings. METHODS Nineteen E. coli isolates that produced CTX-M-type β-lactamase were collected from four communities of elderly people in Shenyang, China. Polymerase chain reaction (PCR) amplification and...

background and objectives: hospital surfaces can serve as reservoirs of potential pathogenic bacteria.staff hands are the main source of bacterial transmission in hospital. the prevalence of bacteria harboring β– lactamase enzyme in staff hands and hospital surfaces, leads to spread of β–lactamase producing bacteria and ultimate increase of antibiotic resistance nosocomial infections. the aim o...

BACKGROUND Co production of 16S rRNA methylases gene and β-Lactamase gene among Enterobacteriaceae isolates conferring resistance to both therapeutic options has serious implications for clinicians worldwide. METHODS To study co existence of 16S rRNA methylases (armA, rmtA, rmtB, rmtC, rmtD, and npmA) and β-Lactamase (blaTEM-1, blaSHV-12, blaCTX-M-14) genes, we screened all phenotypic positiv...

β-Lactamases are produced by many modern bacteria as a mechanism of resistance toward β-lactam antibiotics, the most common antibiotics in use. β-Lactamases, however, are ancient enzymes that originated billions of years ago. Recently, proteins corresponding to 2- to 3-Gy-old Precambrian nodes in the evolution of Class A β-lactamases have been prepared and shown to be moderately efficient promi...

Introduction In this era of modern medicine, antimicrobial resistance can be regarded as a major health calamity. The emergence multidrug-resistant (MDR) Pseudomonas aeruginosa strains poses therapeutic challenges and lead to treatment failure in hospitalized patients. This study was conducted determine various types β-lactamases among MDR P. isolates recovered from patients.
 MethodsThis ...

Enzyme engineering has been facilitated by recombination of close homologues, followed by functional screening. In one such effort, chimeras of two class-A β-lactamases - TEM-1 and PSE-4 - were created according to structure-guided protein recombination and selected for their capacity to promote bacterial proliferation in the presence of ampicillin (Voigt et al., Nat. Struct. Biol. 2002 9:553)....