Abstract:
The kinetics of rhodanese In the liver of domestic fowl was assayed
spectrophotometrically by following the appearance of thiocyanate at 460nm. The
activity of the enzyme was 5.12 umol SCNmin-1g-1 fresh tissues. The activity of the
enzyme was highest at pH 7.0 and 40°C. The activation energy of the enzyme was
calculated to be 2S.53KJ/mol. Double reciprocal plots of the enzyme using varied
concentrations of each of the two substrates suggest that the enzyme may function
through ping-pong mechanism, in which thiosulphate binds first to the enzyme surface
leaving it as a modified sulphurated enzyme, without the formation of a ternary complex,
before the binding of cyanide. These results may reflect the physiological behaviour of
the enzyme.