The effect of quinone toxicity on Chlorococcum, investigated by fast Fourier transformation electrochemical impedance spectroscopy and atomic force microscopy

Abstract

Chlorococcum are simple freshwater or terrestrial microorganisms, which are used for the study of fundamental cellular processes [1]. Chlorococcum is a genus of green algae, which is widely used as a potential source of energy in fuel cells. In our recent research quinone toxicity to Saccaromyces cerevisiae was investigated with a scanning electrochemical microscope in generation-collection mode using a combination of two redox mediators, a lipophilic quinone and hydrophilic potassium ferricyanate [2,3]. It was found that the most effective lipophilic redox mediator was 9,10-phenantrenequinone (PQ), and the UME current in the presence of PQ was about 3 times higher than that registered in the presence of other three redox mediators. The calculation of Hill’s number, which shows the degree of cooperativity, has proved that the maximum PQ cooperativity to yeast cells is at pH 5.5. The same procedures were applied in order to evaluate quinones toxic effect on the Chlorococcum in our present research. Additionally, the damage on Chlorococcum by the quinones was investigated by Fast Fourrier Transform Impedance Spectroscopy. Results revealed the resistance of Chlorococcum to the toxic effect of quinones: Chlorococcum cells contracted, but saved viability. Information about shape of the algae was registered by Atomic Force Microscopy [4] and Optical Microscopy.