Allelic tuning of Slr0320 improves high light acclimation and reveals  an RNA associated regulatory function in Synechocystis
High light disrupts photosystem II (PSII) electron transfer and limits cyanobacterial growth. Slr0320, a predicted cobalamin binding radical S-adenosylmethionine protein, is required for high-light acclimation in Synechocystis sp. PCC 6803, but its physiological role remains unclear. Here, we show that Slr0320 can be functionally tuned by allelic substitution.