Location: Molecular Plant Pathology
Title: Real-time monitoring of the extracellular redox potential of cell suspensions during plant/bacterial interactions Authors
Submitted to: Physiological and Molecular Plant Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 10, 2013
Publication Date: April 1, 2013
Citation: Baker, C.J., Kovalskaya, N.Y., Mock, N.M., Deahl, K.L., Owens, R.A., Whitaker, B.D., Roberts, D.P., Hammond, R., Averyanov, A.A. 2013. Real-time monitoring of the extracellular redox potential of cell suspensions during plant/bacterial interactions. Physiological and Molecular Plant Pathology. 82:20-27. Interpretive Summary: Bacterial plant diseases cause major damage to crops each year and controlling them adds greatly to production costs. The air space inside the plant leaf is the first line of defense against most of these pathogens. Increased knowledge of the molecular interactions that occur at this site can improve resistance and increase yield. In this manuscript we are reporting a new technique to monitor, in ‘real-time’, certain regulatory processes that affect plant resistance. Prior to this, these regulatory ‘triggers’ could not be detected until hours after they occurred. This new precision in timing will allow us to determine how to trigger these regulatory processes more efficiently to improve disease resistance. This information will benefit plant scientists and breeders who are devising new strategies to improve disease resistance in plants.
Technical Abstract: In plants and animals, there has been a strong focus on reactive oxygen species/antioxidants in regard to stress responses. This has lead to an awareness of the importance of ‘redox potential’ as a prime regulatory determinant of cellular function and responses to internal and external stimuli. It has been difficult to study the effect or fluctuation in the redox potential during interactions since most techniques involve metabolite extraction and quantification. We tested a method of using redox electrodes with bacterial and plant cell suspensions to monitor the extracellular redox potential during different plant/bacterial interactions. The advantage of the electrodes is that they are passive in reading the redox potential and interact with a larger array of metabolites, rather than measuring the ratio of oxidative and reductive form of specific chemicals. We found three different responses of redox potential to different plant/pathogen interactions. The responses were related to phenolic changes in the extracellular fluid of the suspensions. Using co-inoculation it was demonstrated that a compatible interaction was able to control the redox response of another bacterial interaction.