Submitted to: Plant Cell Tissue And Organ Culture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 24, 1997
Publication Date: N/A
Interpretive Summary: Increased oxygen uptake is a characteristic early response of plant and animal cells to infection by pathogens. The measurement of oxygen fluxes in cells has been problematic. Often accurate measurement required a closed system that was detrimental to long-term survival of actively respiring cells. The development of the Clark-type oxygen electrode, which produces an electrochemical signal proportional to oxygen concentration in solutions, greatly advanced the study of oxygen in living cell systems. This manuscript describes a method by which up to 16 Clark-type electrodes may be simultaneously monitored using computer hardware and software developed and/or modified in our laboratory. This method is extremely useful in the study of oxygen fluxes during disease processes because it allows the simultaneous monitoring of identical cell suspensions undergoing various treatments and, therefore, insures that proper controls can be incorporated into the experiments. In addition, the system described is open to the atmosphere allowing the monitoring to continue for several hours without subjecting cells to oxygen stress. This method will be of great interest to animal and plant scientists interested in changes in cellular oxygen utilization during normal or disease-induced processes.
Technical Abstract: A method is described that allows the rate of oxygen consumption to be monitored in plant cell suspensions. The method utilized oxygen electrodes placed in beakers of plant cells subjected to various treatments. The voltage readings from calibrated electrodes were converted to % oxygen (100% equals air equilibration) and the rate of oxygen consumption was estimated by calibration graphs made with no cells present. This system simultaneously monitors one to sixteen samples, allowing comparison of treatments on identically treated cells. We have used this method to study the respiratory burst of plant cells produced in response to viable or heat-killed bacteria. Because the system was computer-monitored and open to the atmosphere, data could be collected over several hours. Various factors that affected the measurement of dissolved oxygen concentration with this technique were explored and considered.