Structure of MdfA (IMAGE) Martin-Luther-Universität Halle-Wittenberg Caption The protein MdfA is located in the cell membrane of E. coli. During the structural transformation of one structure into the other (and back), the antibiotic is pumped out of the cell. Credit Milton Stubbs Usage Restrictions Use for covering the research with appropriate credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.