Molecular basis of bacterial resistance to chloramphenicol and florfenicol

Abstract

Chloramphenicol (Cm) and its fluorinated derivative florfenicol (Ff) represent highly potent inhibitors of bacterial protein biosynthesis. As a consequence of the use of Cm in human and veterinary medicine, bacterial pathogens of various species and genera have developed and/or acquired Cm resistance. Ff is solely used in veterinary medicine and has been introduced into clinical use in the mid-1990s. Of the Cm resistance genes known to date, only a small number also mediates resistance to Ff. In this review, we present an overview of the different mechanisms responsible for resistance to Cm and Ff with particular focus on the two different types of chloramphenicol acetyltransferases (CATs), specific exporters and multidrug transporters. Phylogenetic trees of the different CAT proteins and exporter proteins were constructed on the basis of a multisequence alignment. Moreover, information is provided on the mobile genetic elements carrying Cm or Cm/Ff resistance genes to provide a basis for the understanding of the distribution and the spread of Cm resistance--even in the absence of a selective pressure imposed by the use of Cm or Ff.

Functional metagenomic characterization of antibiotic resistance genes in agricultural soils from China

“…arabinofuranosidase like protein conferring chloramphenicol resistance remains unknown. The most common mechanism of chloramphenicol resistance is chloramphenicol acetyltransferases (CATs) mediated by acetylation, resulting in the inactivation of chloramphenicol (Schwarz et al, 2004), however, resistance gene encoding CATs like protein were not detected in this study.…”

Comparison of antimicrobial resistance phenotypes and genotypes in enterotoxigenic Escherichia coli isolated from Australian and Vietnamese pigs

“…Although floR was not detected in either collection, the high prevalence of florfenicol resistance in Vietnamese ETEC isolates may be associated with the cmlA gene, which may be related to historic use of chloramphenicol in livestock and/or co-selection [26]. M a n u s c r i p t…”

Prevalence and molecular characterization of chloramphenicol resistance inRiemerella anatipestiferisolated from ducks and geese in Taiwan

“…Chloramphenicol and its fluorinated derivative florfenicol are antibiotics that inhibit bacterial protein biosynthesis (Schwarz et al, 2004). Chloramphenicol can repress intracellular bacteria by readily traversing biological membranes and the bloodÁbrain barrier (Shaw, 1983).…”

“…Chloramphenicol can repress intracellular bacteria by readily traversing biological membranes and the bloodÁbrain barrier (Shaw, 1983). However, chloramphenicol can be inactivated by two defined types of chloramphenicol acetyltransferases (CATs), type A CATs and type B CATs (Schwarz et al, 2004).…”