Methods using somatic hypermutation (SHM) for producing polypeptide and nucleic acid variants, and nucleic acids encoding such polypeptide variants are disclosed. Such variants may have desired properties. Also disclosed are novel polypeptides, such as improved fluorescent proteins, produced by the novel methods, and nucleic acids, vectors, and host cells comprising such vectors.
This invention was made with government support under Grant No. NS27177, awarded by the National Institutes of Health and Grant NO, DE-FG03-01ER63276, awarded by the Department of Energy. The government has certain rights in this invention.