On suitable observables for the chaotic Peroxidase-Oxidase autocatalytic reaction

Abstract Neurodegenerative diseases such as Alzheimer’s and Parkinson present oxidative damage of neurocytes generally caused by reactive oxygen species (ROS). Heme peroxidases consume and produce ROS thus serving as suppresors and promoters of ROS-related pathology A core reaction network of production and consumption of hydrogen peroxide and superoxide is the Peroxidase-Oxidase (PO). PO reaction was among the first biochemical oscillators to be experimentally and numerically studied, with dynamical scenarios such as multiple steady states, complex oscillations and chaos. In particular, the oxyferrous peroxidase (compound III) and O 2 have been used as observable variables in experiments to record the chaotic dynamics. Moreover, PO reaction has been embedded in nanoparticles in order to serve as a sensor for ROS. In this contribution we quantified, using observability coefficients, which chemical species is more suitable to observe and reconstruct the characteristic complex dynamics of the PO reaction.