Chemicals used in industry and science, in particular proteins including fusion proteins, in particular streptavidin and streptavidin muteins, antibodies, kinases, phosphatases, proteases, G proteins and G protein coupled receptors, peptides, in particular affinity peptides, peptides mediating cell membrane permeation as well as peptides mediating cell and tissue specifity, nucleic acids, in particular nucleic acids encoding the aforementioned proteins and peptides, vectors, in particular exp...