sfGFP is a robustly folded green fluorescent protein which folds when even when fused to poorly folded polypeptides. It is an artificial derivative of the naturally occurring fluorescent protein encoded by the Aequorea victoria GFP gene (UniProtKB:P42212), containing the mutations S30R, Y39N, F64L, S65T, F99S, N105T, Y145F, M153T, V163A, I171V and A206V (PMID:16369541).