GFP(GL) is a green fluorescent protein that is an artificial derivative of the naturally occurring fluorescent protein encoded by the Aequorea victoria GFP gene (UniProtKB:P42212). It contains the S65T mutation (PMID:8676491), which produces a higher fluorescence yield and results in a protein with an excitation peak of 490nm and an emission peak of 510nm in vitro (PMID:7854443). In addition, the coding region has been optimized for human codon usage (PMID:8676491).