Figure 3. Gene expression (top), protein abundance (middle) and enzyme activity (bottom, modified from Tarrant et al. 2021) for citrate synthase (left) and glutamate dehydrogenase (middle) and the first enzyme associated with the electron transport system: NADH dehydrogenase (right). Patterns of transcript expression and protein abundance were not statistically significant in pairwise comparisons (with the exception of NADH dehydrogenase which was significantly higher in the daytime proteome compared to the night time). For each analysis, enzyme activity significantly varied over the course of the day. Clusters of statistical significance are demarcated by letters and error bars represent standard error. Samples collected during the day at depth are demarcated in white while those from the surface at night are in black.