Dennis W. Grogan Professor Ph.D., University of Illinois, Urbana-Champaign Microbiology

THERMOSTABILITY OF SULFOLOBUS ENZYMES

The biosynthetic enzyme orotidine-5'-monophosphate decarboxylase was purified from S. acidocaldarius and its relative activity was assayed as a function of incubation temperature. Under these conditions the maximal activity occurred at about 98º C, with no apparent alteration of activation energy (shown by Arrhenius plot below) over a temperature range of nearly 80º [from publication 9]