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 Q(10)=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 degrees 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.
Valeur
Kirsten Rosendal
KR
Department of Plant Biology and Biochemistry, University of Geneva, 3 Place de l'Université, CH-1211 Geneva 4, Switzerland. krv@combio.dk
degli Agosti
Robert
R
D003198:Computer Simulation; D007700:Kinetics; D008956:Models, Chemical; D009243:NAD / Q000737:chemistry; D010088:Oxidoreductases / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D010544:Peroxidases / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics
D009243:NAD; D010088:Oxidoreductases; D010544:Peroxidases; D010100:Oxygen