Strains of bacteria resistant to antibiotics, particularly those that are multiresistant, are an
increasing major health care problem around the world. It is now abundantly clear that both …

Extended-spectrum β-lactamases (ESBLs) are a rapidly evolving group of β-lactamases
which share the ability to hydrolyze third-generation cephalosporins and aztreonam yet are …

Antimicrobial resistance is one of the major problems in current practical medicine. The
spread of genes coding for resistance determinants among bacteria challenges the use of …

In 2008, a previously unknown Escherichia coli clonal group, sequence type 131 (ST131),
was identified on three continents. Today, ST131 is the predominant E. coli lineage among …

Bacteria carry extrachromosomal, self-replicating genetic elements called plasmids. A
plasmid is defined as a doublestranded, circular DNA molecule capable of autonomous …

In the last 10 years, extended-spectrum β-lactamase-producing enterobacteria (ESBL-E)
have become one of the main challenges for antibiotic treatment of enterobacterial …

In the past decade CTX-M enzymes have become the most prevalent extended-spectrum β-
lactamases, both in nosocomial and in community settings. The insertion sequences (ISs) …

Outbreaks of multidrug-resistant bacteria present a frequent threat to vulnerable patient
populations in hospitals around the world. Intensive care unit (ICU) patients are particularly …

Antimicrobial-modifying resistance enzymes have traditionally been class specific, having
coevolved with the antibiotics they inactivate. Fluoroquinolones, antimicrobial agents used …

Although plasmid-mediated quinolone resistance (PMQR) was thought not to exist before its
discovery in 1998, the past decade has seen an explosion of research characterizing this …