HEAT-STABLE ENZYMES FROM EXTREMELY THERMOPHILIC AND HYPERTHERMOPHILICMICROORGANISMS

Only in the last decade have microorganisms been discovered which grow near or above 100-degrees-C. The enzymes that are formed by these ext remely thermophilic (growth temperature 65 to 85-degrees-C) and hypert hermophilic (growth temperature 85 to 110-degrees-C) microorganisms ar e of great interest. This review covers the extracellular and intracel lular enzymes of these exotic microorganisms that have recently been d escribed. Polymer-hydrolysing enzymes, such as amylolytic, cellulolyti c, hemicellulolytic and proteolytic enzymes, will be discussed. In add ition, the properties of the intracellular enzymes involved in carbohy drate and amino-acid metabolism and DNA-binding and chaperones and cha perone-like proteins from hyperthermophiles are described. Due to the unusual properties of these heat-stable enzymes, they are expected to fill the gap between biological and chemical processes.