Fig. 4: The SOM resembles the upper mixed layer, with key differences in taxonomic composition.
From: Seasonal enhancement of the viral shunt catalyzes a subsurface oxygen maximum in the Sargasso Sea
a Hierarchically clustered heatmap of rpoB/RPB1 normalized transcripts (variance stabilizing transformation, VST) averaged across depth/time collected (day = 8 am, night = 8 pm) and standardized by row (Z-score, ([Observed VST – Mean VST]/standard deviation). VST values are summed across order-level taxonomy for prokaryotes, except for Prochlorococcus and Synechococcus, which are summed to the ecotype-level. VST values are summed across class-level taxonomy for eukaryotes. Each row is color-coded by domain-level taxonomic information. The bar plot to the left shows the total VST for each row across all samples. b Stacked bar plot showing the distribution of transcripts assigned to single-celled amplified genomes (SAGS) from different Prochlorococcus ecotypes across depth. c Maximum Likelihood phylogeny of cyanobacterial genomes. Prochlorococcus ecotypes and Synechococcus genomes detected in the metatranscriptomes are color coded. Stars indicate SAGs that had significantly (BH-adjusted p ≤ 0.1) highest rpoB transcript abundances at the SOM. Because these all fell into the HLI clade, the other clades are collapsed for visual purposes. SAGs and cyanobacterial genomes are from Berube et al.77. Depth layers sampled are surface, defined as 5 m (SRF), base of mixed layer (BML) defined by a change in potential density of 0.125 kg/m3 from a reference pressure of 10 db, the subsurface oxygen maximum (SOM) depth, and the deep chlorophyll maximum (DCM).
