Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)

Editor

Personal info

View

About

Terms

Javascript disabled

Please enable Javascript support in your browser to use this application.

Instructions on how to enable JavaScript on different browsers can be found here: http://www.google.com/support/bin/answer.py?answer=23852.

[edit this page]

Chuanchuen, R. et al.

The MexJK efflux pump of Pseudomonas aeruginosa requires OprM for antibiotic efflux but not for efflux of triclosan.

Using the biocide triclosan as a selective agent, several triclosan-resistant mutants of a susceptible Pseudomonas aeruginosa strain were isolated. Cloning and characterization of a DNA fragment conferring triclosan resistance from one of these mutants revealed a hitherto uncharacterized efflux system of the resistance nodulation cell division (RND) family, which was named MexJK and which is encoded by the mexJK operon. Expression of this operon is negatively regulated by the product of mexL, a gene located upstream of and transcribed divergently from mexJK. The triclosan-resistant mutant contained a single nucleotide change in mexL, which caused an amino acid change in the putative helix-turn-helix domain of MexL. The MexL protein belongs to the TetR family of repressor proteins. The MexJK system effluxed tetracycline and erythromycin but only in the presence of the outer membrane protein channel OprM; OprJ and OprN did not function with MexJK. Triclosan efflux required neither of the outer membrane protein channels tested but necessitated the MexJ membrane fusion protein and the MexK inner membrane RND transporter. The results presented in this study suggest that MexJK may function as a two-component RND pump for triclosan efflux but must associate with OprM to form a tripartite antibiotic efflux system. Furthermore, the results confirm that triclosan is an excellent tool for the study of RND multidrug efflux systems and that this popular biocide therefore readily selects mutants which are cross-resistant with antibiotics.[1]

References

The MexJK efflux pump of Pseudomonas aeruginosa requires OprM for antibiotic efflux but not for efflux of triclosan. Chuanchuen, R., Narasaki, C.T., Schweizer, H.P. J. Bacteriol. (2002) [Pubmed]

Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenes Open Access Licence Privacy Policy Terms of Use apsburg

The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.