Abstract: The invention in at least one embodiment includes a method to convert a fluorescent protein into a modified fluorescent protein in a monomeric state where a dimerization interface is identified in a template protein in a homodimer state. One or more targeted mutation(s) are introduced at the dimerization interface to disrupt dimerization and favor the monomeric state. In another embodiment of the invention, one or more chromophore binding domains are identified in a template protein. One or more targeted mutations are introduced in the chromophore binding domain(s) to change the configuration of a biliverdin chromophore in the template protein from a 15Z anti configuration to a 15E anti configuration.