|
KMID : 0311119980390060520
|
|
Yonsei Medical Journal
1998 Volume.39 No. 6 p.520 ~ p.525
|
|
|
Plasmid-Encoded AmpC β-Lactamases How Far Have We Gone 10 Years after the Discovery?
|
|
Adolf Bauernfeind
Yunsop Chong/Kyungwon Lee
|
|
|
Abstract
|
|
|
|
The dogma that ampC genes are located exclusively on the chromosome was dominant until about 10 years ago. Since 1989 over 15 different plasmid-encoded AmpC β-lactamases have been reported from several countries. Most of these enzymes evolved in two clusters. The major cluster includes several enzymes with a high similarity to CMY-2, which is the closest related chromosomal AmpC enzyme of Citrobacter freundii. A second cluster centers around CMY-1. It is less homogeneous and not closely related chromosomal AmpC enzymes. Molecular diversification by amino acid substitutions does not usually translate into a change in the resistance phenotype. At this time, CMY-2 appears to be the most prevalent and widely distributed. Further global increase of prevalence and diversity of plasmidic AmpC β-lactamases have to be anticipated in the next millenium.
|
|
|
KEYWORD
|
|
|
AmpC β-lactamases, plasmid-encoded β-lactamases, CMY-1, CMY-2, molecular evolution of β-lactamases,
|
|
|
FullTexts / Linksout information
|
|
 
|
|
|
Listed journal information
|
|
   
|