Zam Is a Redox-Regulated Member of the RNB-Family Required for Optimal Photosynthesis in Cyanobacteria.

ABSTRACT: The zam gene mediating resistance to acetazolamide in cyanobacteria was discovered thirty years ago during a drug tolerance screen. We use phylogenetics to show that Zam proteins are distributed across cyanobacteria and that they form their own unique clade of the ribonuclease II/R (RNB) family. Despite being RNB family members, multiple sequence alignments reveal that Zam proteins lack conservation and exhibit extreme degeneracy in the canonical active site-raising questions about their cellular function(s). Several known phenotypes arise from the deletion of zam, including drug resistance, slower growth, and altered pigmentation. Using room-temperature and low-temperature fluorescence and absorption spectroscopy, we show that deletion of zam results in decreased phyc

SUBMITTER: Thomas PE 

PROVIDER: S-EPMC9145284 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature