Antibiotic resistance: multidrug efflux proteins, a common transport mechanism?

The phenomenon of antibiotic resistance in micro-organisms and higher animals including humans, together with the various forms this resistance can take, is discussed. The focus of the review is the resistance, by efflux, to several structurally unrelated antibiotics by multidrug transport proteins. Putative and necessarily differing mechanisms, often supported convincingly by X-ray structural information, are discussed. The review covers the period up to the end of 2004 and contains 75 references.