A Single-Site Mutation Tunes Fluorescence and Chromophorylation of an Orange Fluorescent Cyanobacteriochrome.

ABSTRACT: Cyanobacteriochrome (CBCR) cGMP-specific phosphodiesterase, adenylyl cyclase, and FhlA (GAF) domains bind bilin cofactors to confer sensory wavelengths important for various cyanobacterial photosensory processes. Many isolated GAF domains autocatalytically bind bilins, including the third GAF domain of CBCR Slr1393 from Synechocystis sp. PCC6803, which binds phycoerythrobilin (PEB) to yield a bright orange fluorescent protein. Compared to green fluorescent proteins, the smaller size and lack of an oxygen requirement for fluorescence make Slr1393g3 a promising platform for new genetically encoded fluorescent tools. Slr1393g3, however, shows low PEB binding efficiency (chromophorylation) at ~3 % compared to total Slr1393g3 expressed in E. coli. Here we used site-directed mutagenesis and plas

SUBMITTER: Janis MK 

PROVIDER: S-EPMC10653908 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature