Fig. 4: Cyanovirocell energy and resource metabolic pathways responding to the protist.

A Photosynthesis and phosphate (P) stress. B Central C metabolism, including mannose synthesis, glycolysis, galactose metabolism pentose phosphate pathway (PPP), Calvin cycle, and the Tricarboxylic acid (TCA) cycle. C De novo purine and pyrimidine nucleotide synthesis. Phage auxiliary metabolic genes (AMGs) are in green text. Host over-expressed genes are in purple, while the under-expressed one is in red. The color of the arrow or the border (orange or blue) denotes if the gene is expressed in response to phage only or phage and protist. Metabolites that change significantly have a background shade colored red (if enriched) or yellow (if depleted) and the position of the shade denotes under which treatment they are altered: in the cyanovirocells only or in the cyanovirocells co-cultured with protists. D Photosynthetic efficiency of Synechococcus cells under each condition. Asterisks indicate when treatments are significantly different (t-test, p value <0.05). Cyanovirocells and cyanovirocells with protist both have significantly lower photosynthetic efficiency than uninfected cells (red and blue arrows with asterisks, respectively), but cells with just the protist do not (t-test, p value >0.05). Cyanovirocells with protist significantly increase in photosynthetic efficiency from ~2 to ~5 h post infection relative to cyanovirocells alone (t-test, p value <0.05). Abbreviations can be found in the Supplementary text.