Small, soluble single-domain fragments derived from the unique variable region of dromedary heavy-chain antibodies (VHHs) against enzymes are known to be potent inhibitors. The immunization of dromedaries with the TEM-1 and BcII beta-lactamases has lead to the isolation of such single-domain antibody fragments specifically recognizing and inhibiting those beta-lactamases. Two VHHs were isolated...

The properties of cefazolin, cefoxitin, cefamandole, and cefuroxime have been compared with those of cephaloridine, cephalothin, and cephalexin. The properties included for examination are the susceptibility to a range of beta-lactamases commonly encountered in gram-negative species and the ability of a beta-lactam antibiotic to penetrate the outer layers of Escherichia coli. Of the antibiotics...

Respiratory isolates of Klebsiella pneumoniae in Korea during 2002-2003 were studied to determine the prevalence and types of extended-spectrum beta-lactamases (ESBLs) and plasmid-mediated AmpC beta-lactamases (PABLs). ESBL-production was tested by double-disk synergy, and genotypes of beta-lactamases were determined by PCR and sequencing. ESBLs were detected in 28.4% of 373 isolates, and the m...

Many clinical laboratories have problems detecting extended-spectrum beta-lactamases (ESBLs) and plasmid-mediated AmpC beta-lactamases. Confusion exists about the importance of these resistance mechanisms, optimal test methods, and appropriate reporting conventions. Failure to detect these enzymes has contributed to their uncontrolled spread and sometimes to therapeutic failures. Although Natio...

Infections caused by bacteria have a significant impact on public health. Chemical synthesis of new derivatives cephalexin inked to amino acid (tryptophan or histidine) through an amide bond at the acyl side chain is achieved. This new
 approach incorporating, tryptophan and histidine into primary group cephalexin, in order provide bulky very close ?-lactam ring. chemical addition act as i...

Previous studies in this and other laboratories have shown that derepression of beta-lactamases in strains of Enterobacter and Pseudomonas spp. is responsible for the rapid development of resistance to a variety of beta-lactam antibiotics. The purpose of the current study was to evaluate the effects of clindamycin on derepression of beta-lactamases in these two genera. In tests with four strain...

Ligase chain reaction (LCR) is a recently developed technique that employs a thermostable ligase and allows for the discrimination of DNA sequences differing in only a single base pair. The method has been adapted and applied to differentiation of bla(SHV) genes. We have developed an LCR typing method to characterize point mutations in genes for SHV-derived extended-spectrum beta-lactamases wit...

Cephanone is less active against gram-positive organisms but is more active against Escherichia coli than cephalothin. Activity against Klebsiella, Proteus mirabilis and Salmonella is similar to cephalothin. Some Enterobacter strains are"susceptible to 8//g/ml or less. Cephanone is relatively resistant to hydrolysis by gram-negative beta-lactamases. It is not a competitive inhibitor of the hydr...

Aims: This study aimed to screen for Beta Lactamases (BLs) and other resistant bacteria among patients admitted the emergency unit of Yaoundé University Teaching Hospital (YUTH).
 Study Design: was a cross-sectional hospital-based study.
 Place Duration Study: conducted at Bacteriology YUTH, Yaoundé- Cameroon between February June 2020.
 Methodology: Seventy-Five urine samples we...

Important discrepancies in isoelectric points (pI) of beta-lactamases were observed depending on the experimental procedure used for their determination: isoelectric focusing (IEF) in sucrose density gradients or analytical IEF in thin-layer polyacrylamide gels (PA). The variations, negligable in the case of TEM-like beta-lactamases, appeared to be important in the case of cephalosporinases and...