GENERAL ⎜ ARTICLE
RESONANCE ⎜ March 1998
Extremozymes that function in the extreme environ-
mental conditions of temperature, pressure, pH, and
salinity are of great importance for industrial processes
and scientific research. Apart from understanding the
principle behind the stability of such enzymes, there has
been considerable effort to isolate enzymes from
extremophiles (organisms that live in extreme environ-
mental conditions) as well as modify enzymes from
mesophiles (organisms that live in normal environmental
conditions) to convert them into extremozymes.
Enzymes are biocatalytic protein molecules that enhance the
rates of biological reactions by 106 to 1023 fold over the uncataly-
zed reactions. A number of enzymes have been isolated from
organisms for a variety of industrial processes and scientific
research. Glucose isomerase, amylase, lipase and proteases are
used in a variety of food, beverages and soap and detergent
industries, while Taq polymerase T4 lysozyme, ribonuclease and
malate dehydrogenase are enzymes used in research laboratories.
A major limitation of most enzymes used in the industries/
research laboratories is that they are very unstable even under
ambient temperature let alone extreme conditions of temperature,
pressure and pH. But life exists in extreme conditions of the
environment like glaciers, hot springs, deep seas and the Dead
Sea. Thus the metabolism and the nature of enzymes from these
organisms, collectively called extremophiles, are likely to help
us understand and manipulate protein stability. Thus there is
not only a need to search for enzymes from extremophiles but also
to understand the basis of the tolerance of naturally occurring
extremozymes to high temperature or pH so that enzymes from
mesophiles can be engineered to behave like extremozymes.
Enzyme Vs. Extremozyme
What Makes Extremozymes Function Under Harsh Conditions ?
Santosh Kumar is doing
his Ph D at Biotechnology
Centre, Indian Institute of
Technology, Bombay .
His research inte