What is the structure of green fluorescent protein (GFP)?

Green Fluorescent Protein possesses a cylindrical shape formed by 11 strands of beta-sheet arranged around an alpha-helix situated inside. Additionally, there are short helical segments located at both ends of the cylinder. This unique structure makes up a novel protein fold known as the beta-can. Two individual units of the protein come together tightly to form a dimer when observed in its crystal form.