A genetic circuit system based on quorum sensing signaling for directed evolution of quorum-quenching enzymes.
Quorum sensing is a cell-cell communication mechanism that is involved in the regulation of biological functions such as luminescence, virulence, and biofilm formation. Quorum-quenching enzymes, which interrupt quorum-sensing signaling through degradation of quorum-sensing molecules, have emerged as a new approach to controlling and preventing bacterial virulence and pathogenesis. In an effort to develop quorum-quenching enzymes with improved catalytic activities, a genetic circuit system based on acylhomoserine-lactone (AHL)-mediated quorum-sensing signaling was constructed. The genetic circuit system was composed of lux-R, lux-I promoter, beta-lactamase, and beta-lactamase inhibitor, and designed to confer antibiotic resistance on host cells expressing an AHL-degrading enzyme, thereby enabling rapid screening of quorum-quenching enzymes. To demonstrate the utility of the genetic circuit system, we attempted the directed evolution of the AHL hydrolase from Bacillus sp. The genetic circuit system was shown to be effective in screening of quorum-quenching enzymes with high catalytic efficiency. From these results it is expected that the genetic circuit system can be widely used for the isolation and directed evolution of quorum-quenching enzymes with greater potential.
Kim
Jin-Hyun
JH
Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon, 305-701, Korea.
Lee
Sang-Chul
SC
Kyeong
Hyun-Ho
HH
Kim
Hak-Sung
HS
D001407:Bacillus / Q000201:enzymology* / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics; D019020:Directed Molecular Evolution; D007783:Lactones / Q000378:metabolism*; D053038:Quorum Sensing / Q000235:genetics / Q000502:physiology*; D012097:Repressor Proteins / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology*; D015534:Trans-Activators / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics; D001618:beta-Lactamases / Q000235:genetics
D001426:Bacterial Proteins; D007783:Lactones; C085427:LuxI protein, Bacteria; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C064778:LuxR autoinducer binding proteins; D001618:beta-Lactamases