الفهرس | Only 14 pages are availabe for public view |
Abstract Summary Gram-negative bacteria are found everywhere, in virtually all environments on Earth that support life. The gram-negative bacteria include Escherichia coli, Klebsiella, Pseudomonas aeruginosa, Neisseria , proteus and salmonella. The rapid increase in antimicrobial resistance of pathogenic bacteria is a major problem. The increasing incidence is due to the frequent use of antibiotics while the patients are in critical condition. There are multiple mechanisms of antibiotic resistance; the most common one is the production of Beta-Lactamase which can inactivate antibiotics by hydrolyzing the amide bond of its Beta-Lactam ring. Beta-Lactamases are divided into four classes (A,B,C and D) based on their molecular structure , class A,C and D are serine Beta lactamases which require serine residue on their active site and Class B, called Metallo-Beta-lactamases (MBL) which requires one or two zinc ions in their active site. MBL can hydrolyze all Beta lactam antibiotics, but its action can be inhibited by metal chelators such as EDTA and Thiol. Metallo Beta Lactamase producing bacteria are gradually increasing throughout the globe, and considered a real threat that result in high mortality rate. This study aimed to asses efficiency of some phenotypic and genotypic tests for rapid detection of MBLs among gram negative bacilli (GNB), and also to determine the proportion of MBL producing bacteria among GNB. This was achieved by phenotypic methods as double disc synergy test (DDST) using metal chelators as EDTA. |