metal ions are the main impurities of water and media ingredients used in fermentation processes. in this research, the effect of ca+2, co+2, cu+2, fe+2, mg+2, mn+2 and zn+2 as chloride and sulfate salts was studied on the clavulanic acid production and streptomyces clavuligerus growth. all chloride salts had negative effect on clavulanic acid production and no clavulanic acid was produced in t...

b ackground : the emergence and rapid spread of metallo-beta-lactamase (mbl) producing acinetobacter spp. are of great concern worldwide due to limited treatment options. epidemiologic studies of the causing genes are important for prevention. methods :   in  this  study,  70  imipenem-resistant  acinetobacter  strains  were isolated from health care associated infections. these isolates were s...

Induction of ampC β-lactamase expression can often compromise antibiotic treatment and is triggered by several β-lactams (such as cefoxitin and imipenem) and by the β-lactamase inhibitor clavulanic acid. The novel β-lactamase inhibitor avibactam (NXL104) is a potent inhibitor of both class A and class C enzymes. The potential of avibactam for induction of ampC expression in Enterobacter cloacae...

INTRODUCTION .......................................................................................................................................................161 MECHANISM OF ACTION OF -LACTAM ANTIBIOTICS .............................................................................161 RESISTANCE TO -LACTAM ANTIBIOTICS ..........................................................................

Combination of lactam antibiotic with lactamase inhibitor has been proven to overcome resistance caused by lactamase production. An evaluation to the MIC of some lactam antibiotics to b-lactamase producing isolates will be reported. A.anitratus, E.coli, K.pneumoniae, Proteus sp, Pseudomonas sp, S.aureus, S.epidermidis, S.pneumoniae, S.viridans, and hemolytic Streptococcus, were challe...

Antimicrobial combination therapy is a time/resource-intensive procedure commonly employed in the treatment of cystic fibrosis (CF) pulmonary exacerbations caused by Pseudomonas aeruginosa . Ten years ago, most promising antimicrobial combinations were proposed, but there has since been introduction new ?-lactam plus ?-lactamase inhibitor combinations.

Vaborbactam (formerly RPX7009) is a new beta-lactamase inhibitor based on a cyclic boronic acid pharmacophore. The spectrum of beta-lactamase inhibition by vaborbactam and the impact of bacterial efflux and permeability on its activity were determined using a panel of strains with beta-lactamases cloned from various classes and a panel of Klebsiella pneumoniae carbapenemase 3 (KPC-3)-producing ...

Enterobacter aerogenes clinical isolate LOR was resistant to penicillins and ceftazidime but susceptible to cefuroxime, cephalothin, cefoxitin, cefotaxime, ceftriaxone, and cefepime. PCR and cloning experiments from this strain identified a novel TEM-type beta-lactamase (TEM-121) differing by five amino acid substitutions from beta-lactamase TEM-2 (Glu104Lys, Arg164Ser, Ala237Thr, Glu240Lys, an...