The last 5 to 6 years have witnessed an outburst of renewed interest in the beta-lactam antibiotics. One of the main factors contributing to this was the introduction of the simple and powerful technique of sodium dodecyl sulphate electrophoresis for the identification of bacterial membrane components--penicillin binding proteins--that bind radioactive penicillin and most likely represent the primary biochemical targets of penicillin action in the bacterial cell. Application of this technique has led to a remarkable number of novel observations that have substantially modified our view of the mode of action of beta-lactam antibiotics.
