SPA-GFP encodes a photoactivatable derivative of the naturally occurring fluorescent protein encoded by the Aequorea victoria GFP gene (UniProtKB:P42212). It was identified in a screen for mutations of the canonical photoactivatable fluorophore PA-GFP with improved diffusional and folding properties, and incorporates nine additional mutations (S30R, Y39N, A206V, M153T, Y145F, V163A, I171V, F99S and N105T) identified in 'Superfolder' sfGFP. SPA-GFP does not include the EGFP mutations F64L and S65T, which disrupt the ability to undergo photoactivation (FBrf0212443).