What is the optimum temperature for catalyses?

For any chemical reaction, the reaction rate enhances with temperature, so the higher the temperature, the faster the rate. For any enzymatic reaction, the reaction rate will enhance with temperature unless the temperature at which the enzyme starts to denature is reached, and this is the optimum temperature.

The denaturizing temperature depends on the composition of the protein (its amino acid sequence), which differs for catalyses from different organisms. Therefore, the answer to your question is that the optimum temperature is dependent on the source organism.