Emory University

Kathryn Gay

David S Stephens

Macrolide resistance associated with macrolide efflux (mef) inhas been defined with respect to the genetic structure and dissemination of a novel mefE-containing chromosomal insertion element. The mefE gene is found on the 5'-end of a 5.5 kb or 5.4 kb insertion designated mega (acrolideffluxeneticssembly) found in at least four distinct sites of the pneumococcal genome. The element is transformable and confers macrolide resistance to susceptible. The first two open reading frames (ORFs) of the element form an operon composed of mefE and a predicted ATP-binding cassette homologous to msrA. Convergent to this efflux operon are three ORFs with homology to stress response genes of Tn5252. Mega is related to mefA-containing element Tn1207.1. Macrolide resistance due to mega has been rapidly increased by clonal expansion of bacteria containing it and horizontally by transformation of previously sensitive bacteria.

Growing community of inventors

Atlanta, GA, United States of America

Kathryn Gay