At what temperature can enzymes maintain their catalytic activity?

It was shown by the combination of thermogravimetric analysis and Karl Fish er titrations that temperatures in excess of 200 degrees C are required to remove tightly bound water from proteins. The heating of enzymes to this te mperature caused no cleavage of the polypeptide chains and very little, if any, chemical degradation of particular amino acid residues as judged by el ectrophoretic and amino acid analysis respectively. It was hypothesised tha t those enzymes that require very little water for their catalytic activity , should remain active at such elevated temperatures provided that they can be stabilised against thermodenaturation. This conclusion has been verifie d by the observation that immobilised Candida antarctica lipase catalysed t ransesterification of octadecanol with palmityl stearate at 130C for a cons iderable period of time. (C) 2000 Elsevier Science Inc. All rights reserved .