Rv. Rariy et al., HIGH-PRESSURE STABILIZATION OF ALPHA-CHYMOTRYPSIN ENTRAPPED IN REVERSED MICELLES OF AEROSOL OT IN OCTANE AGAINST THERMAL INACTIVATION, FEBS letters, 364(1), 1995, pp. 98-100
alpha-Chymotrypsin (CT) solubilized in reversed micelles of sodium bis
-(2-ethylhexyl)-sulfosuccinate (AOT) undergoes thermal inactivation an
d the enzyme stability decreases significantly when temperature increa
ses (25-40 degrees C). The half-life of CT in micelles shows a bell-sh
aped dependence on the degree of hydration of AOT (w(o)) analogous to
the previously obtained dependence on w(o) for the enzyme activity. Th
e optima of catalytic activity and thermal stability have been observe
d under conditions where the diameter of the inner aqueous cavity of t
he micelle is close to the size of the enzyme molecule (w(o) = 10). Ap
plication of high hydrostatic pressure in the range of 1-1500 atm (bar
) stabilizes CT against thermal inactivation at all hydration degrees
(w(o)) from 7 to 20; the stabilization effect is most pronounced under
the experimental conditions being far from the optimum for catalytic
activity.