mBaoJin is a monomeric green fluorescent protein with an excitation peak of 500nm and an emission peak of 508nm in vitro. It is an artificial derivative of the naturally occurring fluorescent protein encoded by the Cytaeis uchidae CU17S gene (GB:LC593677), derived by mutagenesis of StayGold. mBaoJin shows high brightness and photostability. (PMID:38409224).