Bursting oscillations in an enzyme model reaction system

Marcus Hauser, Abteilung Biophysik, Institut für Experimentelle Physik, Otto-von-Guericke-Universität Magdeburg

Bursting oscillations are wide-spread dynamics observed in a variety of biological systems. Bursting oscillations – as well as mixed-mode oscillations – are composed of oscillatory cycles where the large- and the small-amplitude excursions occur on different amplitude scales.

We study dynamical behaviour of an enzyme model reaction system that induces pronounced oscillations in the pH value of the reaction medium. We investigate the rich dynamics as a function of the supply rate of substrates. One topic of interest is the investigation of the origin of bursting dynamics. To this purpose, applying the method of first integrals, we reduce the mechanism to a 3-variable version which is then used to investigate the origin of bursting dynamics.

pH is a property that may sensitively affect key physiological (and technical) parameters in the environment of the oscillating system. Therefore, a coupling of a pH sensitive system to the enzyme model system hold promises for a variety of applications. The fundamental effects of such a coupling on the dynamics of the enzyme model system are presented.