Respiratory electron transport activities in phytoplankton and bacteria: Comparison of methods1

Abstract

Six methods of measuring the activity of the respiratory electron transport system (ETS) were intercalibrated using cultures of algae and bacteria and natural plankton assemblages from Lake Washington and Puget Sound. The ETS methods fall into a group that uses the detergent Triton X‐100 and a group that does not. Within either group, the methods yielded similar results. Between the groups, the results differed 4–10‐fold, the detergent‐containing methods having the greater activity. Conversion tables are given to compare the results of one assay with another. The results show that differences in the published relationships between ETS activity and respiration in phytoplankton‐dominated plankton samples are largely explained by methodology.