* Review the different types of extended spectrum beta-lactamases (ESBLs), cephalosporinases
, and carbapenemases that may be present in Gram-negative bacilli.
For checking the production of cephalosporinase
enzyme bacterial lawn was prepared on MH agar and 30g discs of Ceftazidime Cefuroxime Cefotaxime and Aztreonam were placed for 24 hours on 370C.
Regarding the antimicrobial susceptibility, non-wild type (100% of strains) was observed with ofloxacin (MIC = 1 mg/mL and [less than or equal to] 0.5 mg/L), ciprofloxacin (MIC [less than or equal to] 0.5 mg/L) and ertapenem (MIC = 1 mg/mL and [less than or equal to] 0.5 mg/L) (Table 3), while 41.02% of isolated strains were resisted to beta-lactam (aminopinicillinase, cephalosporinase
) justified by different resistance profiles with three strains exhibited an extended spectrum beta-lactamase (ESBL) responsible for resistance to third-generation cephalosporins (C3G) confirmed by a synergy between the antibiotics discs amoxicillin-clavulanic acid and cefotaxim/ceftazidime.
Misinformed antibiotic policy influenced not only the selection of carbapenem-resistant subpopulations but also the production of [beta]-lactamases (e.g., imipenem is a strong inducer of AmpC cephalosporinase
) [8, 10].
However, a combination of a new cephalosporinase
and penicillinase provides inactivation of a broad spectrum of 13-lactam antibiotics, including cephalosporins of the third and fourth generation.
Identification of a new allelic variant of the Acinetobacter baumannii cephalosporinase
, ADC-7 [beta]-lactamase: defining a unique family of Class C enzymes.
aeruginosa is an inducible cephalosporinase
that confers resistance to all betalactams except the carbapenems.
Tran, Q T , Dupont, M , Lavigne, J P , Chevalier, J , Pages, J M , Sotto, A , Anne Reglil, D 2009 Occurrence of Efflux Mechanism and Cephalosporinase
1 Variant in a Population of Enterobacter aerogenes and Klebsiella pneumoniae Producing Extended-Spectrum a-Lactamases Antimicrobials Agents and Chemotherapy On line doi:10 1128/ AAC 00822-08
alteration of penicillin binding site, beta-lactamase and extended-spectrum beta-lactamase-producing organisms via chromosomal-inducible enzymes and cephalosporinase
, ribosomal site alteration, efflux mediated mef E (high level) and target modifiable erm AM mediated (low level) resistance, alteration in the binding site of a specific transpeptidase (mec A) in methicillin-resistant S.
The presence of extended-spectrum cephalosporinase
activity was evaluated within Puerto Rico using surrogate markers of cephalosporin susceptibilities across generations (Table 2).
Penicillin and cephalosporins are not recommended for initial treatment due to the demonstration of a cephalosporinase
and an inducible penicillinase in the anthrax genome.
anthracis strains produce a cephalosporinase
and suggest that the strains contain an inducible beta-lactamase that might decrease the effectiveness of penicillins, especially when a large number of organisms is present (2).
Genetic characterization of an extended-spectrum AmpC cephalosporinase
with hydrolysing activity against fourth-generation cephalosporins in a clinical isolate of Enterobacter aerogenes selected in vivo.