Structure of Macrolide Efflux Protein (MefA/E) inStreptococcus pneumoniae: An in silico approach

Background Macrolides are one of the commonest antibiotics used to treat bacterial respiratory tract infections. Resistance to this class of antibiotics is on the rise and is mediated by macrolide efflux (MefA/E) protein as one of the mechanisms. Despite its importance, the structure of this protein is not known yet. Methods The publicly available MefA/E protein sequence was used to model the structure. Modelling was performed in I-TASSER, and the model was further refined. Its orientation in a membrane was studied using OPM server. Results and conclusions The structure of MefA/E resembled that of Major Facilitator Superfamily (MFS) proteins, with 13 transmembrane helices. It had a V-shaped conformation, with the wider part towards the outer membrane layer.