BACKGROUND & OBJECTIVES Pseudomonas aeruginosa possessing chromosomally inducible blaPDCalong with other intrinsic mechanism causes infection with high mortality rate. It is difficult to detect inducible AmpC enzymes in this organism and is usually overlooked by routine testing that may lead to therapeutic failure. Therefore, three different inducers were evaluated in the present study to asses...

Three Haemophilus parainfluenzae strains isolated from the urogenital tract harbored a beta-lactamase-coding 3.2-megadalton plasmid identical, by restriction endonuclease digestion and hybridization with radioactive and biotin-labeled probes specific for the TEM-1 beta-lactamase and TnA sequences, to the 3.2-megadalton "African-type" plasmid found in Neisseria gonorrhoeae.

In the previous paper1), we reported the comparative study of the enzymatic and physicochemical properties of a novel 3-lactamase produced by Bacteroides fragilis G-237 with those of a typical B. fragilis /3-lactamase produced by B. fragilis G-242. The enzyme produced by B. fragilis G-237 showed a unique substrate profile in hydrolyzing cephalosporins including 7amethoxycephalosporins, penicill...

Despite the fact that P-lactamases from a range of bacterial species Gram-positive and Gram-negative show evolutionary relatedness, there is no set pattern to the genetic organization that underlies their synthesis and its regulation. Thus, for example, the enzymes of many Gram-positive species are extracellular and inducible, whereas their counterparts in Gram-negative bacteria are often produ...

Despite the fact that P-lactamases from a range of bacterial species Gram-positive and Gram-negative show evolutionary relatedness, there is no set pattern to the genetic organization that underlies their synthesis and its regulation. Thus, for example, the enzymes of many Gram-positive species are extracellular and inducible, whereas their counterparts in Gram-negative bacteria are often produ...

Carbapenem-hydrolyzing -lactamases can be metallolactamases (7), expanded-spectrum oxacillinases (8), or Ambler class A enzymes (1, 2, 4, 6, 9–12). The class A KPC -lactamases hydrolyze all -lactams except for cephamycins and have been rarely reported in studies of enterobacterial species (Klebsiella pneumoniae, Klebsiella oxytoca, Salmonella enterica, Enterobacter sp.) found in New England and...

The production of β-lactamase enzymes is one of the most distributed resistance mechanisms towards β-lactam antibiotics. Metallo-β-lactamases constitute a worrisome group of these kinds of enzymes, since they present a broad spectrum profile, being able to hydrolyze not only penicillins, but also the latest generation of cephalosporins and carbapenems, which constitute at present the last resou...