Plant Respiration and Internal Oxygen

Peter Keil, Gregor Liebsch, Ljudmilla Borisjuk, Hardy Rolletschek

The high-throughput analysis of respiratory activity has become an important component of many biological investigations. Here, a technological platform, denoted the "MultiSense tool," is described. The tool enables the parallel monitoring of respiration in 100 samples over an extended time period, by dynamically tracking the concentrations of oxygen (O2) and/or carbon dioxide (CO2) and/or pH within an airtight vial. Its flexible design supports the quantification of respiration based on either oxygen consumption or carbon dioxide release, thereby allowing for the determination of the physiologically significant respiratory quotient (the ratio between the quantities of CO2 released and the O2 consumed). It requires an LED light source to be mounted above the sample, together with a CCD camera system, adjusted to enable the capture of analyte-specific wavelengths, and fluorescent sensor spots inserted into the sample vial. Here, a demonstration is given of the use of the MultiSense tool to quantify respiration in imbibing plant seeds, for which an appropriate step-by-step protocol is provided. The technology can be easily adapted for a wide range of applications, including the monitoring of gas exchange in any kind of liquid culture system (algae, embryo and tissue culture, cell suspensions, microbial cultures).