Simulations of temperature sensitivity of the peroxidase–oxidase oscillator

The influence of temperature on the oscillatory kinetics of the peroxidase–oxidase reaction was studied theoretically. Assuming Q10=2 for elementary reactions, the effect of multiplying the rate constants of the model by factors between 0.5 and 2 (corresponding to a 10 °C decrease and increase, respectively, of temperature) was investigated. First, the individual rate constants were successively multiplied by 0.5 or 2 while all other rate constants were kept unchanged. This resulted in either a longer or a shorter period, depending on the rate constant being changed. Multiplication by 0.5 or by 2 generally resulted in opposite effects on the period length. However, the absolute value of this deviation differed. Also, the dynamics changed when halving the dimerization rate of NAD as well as when doubling the rate constant for the reduction of ferric peroxidase by NAD. Next, simulations were performed multiplying all rate constants by one and the same factor, which increased progressively from 0.5 to 2. Intervals were found corresponding to temperature dependency, compensation, and over-compensation, respectively.