Oceanic photosynthesis is directly affected by cyanophage NblA proteins - whole cell proteome changes

Marine picocyanobacteria are abundant and globally significant photosynthetic organisms that coexist in the ocean with cyanophages, viruses that infect cyanobacteria. Cyanophages carry auxiliary metabolic genes acquired from their hosts, which are thought to reprogram host metabolism to benefit the phage. One such gene is nblA, found across multiple cyanophage families. In cyanobacteria, nblA is responsible for triggering the proteolytic degradation of the phycobilisome—the large light-harvesting complex essential for photosynthesis—under nutrient deprivation. In this study, we characterized the proteomic changes in Synechococcus sp. strain WH8109 following infection with wild-type cyanophage S-TIP37, a T7-like phage isolated from the Red Sea, and compared these changes to those observed with an S-TIP37 mutant lacking the nblA gene.