TY - JOUR
TI - KINETIC EVIDENCE FOR THE EXISTENCE OF AN UNSTABLE INTERMEDIATE IN THE
TRINITROPHENYLATION-INDUCED RHODANESE INACTIVATION REACTION
AU - RAKITZIS, ET
AU - MALLIOPOULOU, TB
JO - International Journal of Biochemistry
PY - 1992
VL - 24
TODO - 7
SP - 1051-1055
PB - PERGAMON-ELSEVIER SCIENCE LTD
SN - 0020-711X
TODO - 10.1016/0020-711X(92)90373-9
TODO - null
TODO - 1. Rhodanese inactivation by 2,4,6-trinitrobenzenesulphonate, in the
presence of n-butylamine in the reaction medium, has been studied by a
kinetic analysis of the data, based on the assumption that enzyme
inactivation is brought about by direct reaction of this with the
modifying agent.
2. Initial reaction rates for rhodanese activity loss were determined by
a mathematical analysis of the first three recorded values of rhodanese
residual activity.
3. It was found that fractional rhodanese activity values, at infinite
reaction time with 2,4,6-trinitrobenzenesulphonate (end-point values),
were significantly lower than the values calculated on the assumption of
rhodanese inactivation being entirely due to direct trinitrophenylation
of enzyme protein.
4. Also, initial enzyme inactivation values were higher in the presence,
rather than in the absence, of n-butylamine.
5. These results indicate that 2,4,6-trinitrobenzenesulphonate-induced
rhodanese inactivation, in the presence of n-butylamine in the reaction
medium, is due to the generation of a highly reactive, unstable
intermediate, probably a free radical species.
ER -