The influence of surfactants on enzyme activity

Most of the recent literature on the effect of surfactants on enzyme activity focuses on enzymes that function at interfaces. Model studies on substrates in solution and at solid/liquid interfaces are beginning to reveal the relationship between such fundamental parameters as surface concentration, surface mobility and enzyme kinetics. For enzymes that function at liquid/liquid interfaces, such as lipases and phospholipases, the recent increase in the number of X-ray structures combined with site-directed mutagenesis studies has resulted in a clearer picture of the molecular events responsible for catalysis. The influence of surfactants on the enzyme structure and the environment in which the enzyme must function is still not as well defined as one would wish, although significant progress has been made. The activity of integral membrane proteins can be strongly influenced by the surfactant systems used in their isolation. The way in which surfactants inhibit or augment such activity is beginning to emerge in a number of individual cases.