Synthesis of AcPheLeuNH(2) by alpha-chymotrypsin in TTAB reversed micelles: Application of response surface methodology to the optimization of the system.
The influence of the long chain alcohols, hexanol, octanol, and decanol, as cosurfactants of the reverse micellar system of tetradecyltrimethylammonium bromide on the alpha-chymotrypsin-mediated AcPheLeuNH(2) synthesis was studied. The effect of temperature, buffer molarity, pH, and substrate concentration was also evaluated. The enzyme was chemically modified and the effect of this modification upon the enzyme activity was also analyzed. Octanol allowed a higher activity for both enzyme forms. The peptide synthesis/substrate hydrolysis ratio is independent of the long chain alcohol used. The chemical modification decreases the alpha-chymotrypsin activity under the system conditions studied, but increases the initial velocity of peptide synthesis relative to the ester substrate hydrolysis. The response surface methodology was applied to optimize the dipeptide synthesis in the system containing octanol as cosurfactant. (c) 1994 John Wiley & Sons, Inc.
Serralheiro
M L
ML
Laboratório de Engenharia Bioquímica, Instituto Superior Técnico, Av. Rovisco Pais, 1000 Lisboa, Portugal.
Cabral
J M
JM