TWO BIOCHEMICAL OSCILLATORS COUPLED BY MASS EXCHANGE

We present experiments and simulations of two mutually mass-coupled biochemical oscillators represented by the nonlinear peroxidase-oxidase reaction. The uncoupled oscillators show simple period-1 (P1) oscillations of different frequencies for different values of the oxygen concentration in the gas stream. A phase diagram is established where the ratio of the natural frequencies is plotted versus the mass exchange rate. For each frequency ratio four regimes of behavior have been observed for an increasing mass exchange rate:  (I) two independent and uncorrelated P1 oscillations; (II) quasiperiodicity in one and P1 oscillations in the other reactor; (III) quasiperiodicity in both reactors; (IV) periodic in-phase synchronization of both reactors. We use the correlation coefficient, the frequencies of the system, and the phase difference between the two cells to characterize the four regimes. A new feature of this work is the experimental observation of an “infinite” modulation period at the transition from ...