Mobile Gene Elements Contribute to Drug Resistance

Genome analysis has revealed that "mobile elements,” small segments of DNA that can jump between organisms or their chromosomes, play an important role in the rapid development of drug resistance by Enterococcus faecalis. A study reporting these findings was published in the March 28, 2003, issue of Science.

A large team of investigators at The Institute for Genomic Research (Rockville, MD, USA) sequenced and analyzed the complete genome of E faecalis V583, a strain that is resistant to the antibiotic vancomycin. Their analysis found that nearly a third of the 3.2 million base pair E faecalis genome consisted of mobile or ‘foreign' DNA. This portion of the genome included three plasmids as well as multiple remnants of phage, plasmids, and other mobile elements, including transposons. Two sites related to vancomycin resistance or tolerance were identified.

Senior author Dr. Claire M. Fraser, director of The Institute for Genomic Research explained, "The identification of a novel vancomycin-resistant transposon in E faecalis demonstrates the power of genomics to reveal new insights into the biology of important human pathogens. This information is critically important in the search for new antibiotics and vaccines to combat infectious diseases.”



Related Links:
The Institute for Genomic Research