Fig. 6: Iron-rich mitochondrial processes are preferentially maintained over plastid processes.

a Box plot of mean log₂(−Fe/+Fe) abundance of protein subunits in the photosynthesis ETC (x-axis, “Photosynthesis”, n = 64 proteins) vs. the respiratory ETC (“Respiration”, n = 97 proteins) in every Glc and strain combination. The box represents first to third quartile (Q1 & Q3) with median as center line, while the whiskers represent local minimum (Q1 X 1.5 X interquartile range) and maximum (Q3 X 1.5 X interquartile range). Individual points for each subunit are shown. Red points are subunits known to bind to an iron cofactor (heme, Fe-S cluster, non-heme iron). The p value for the Wilcoxon Rank Sum Test comparing Fe fold change difference of Photosynthesis vs. Respiration is shown for each Glc and strain combination. The Photosynthesis outlier FLD1 (flavodoxin 1) is labeled which is upregulated in all −Fe conditions. b Protein heatmap (left) and model of iron-trafficking components in C. zofingiensis (right). The high-affinity iron assimilation pathway components were highly upregulated in −Fe and localize to the plasma membrane or periplasm³⁷. The transporter orthologs IRT1 and FTR1 occur in the C. zofingiensis genome but were not detected in enough conditions to make interpretations on their regulation. Source data are provided in the Source Data File.