The video describes the background to the origin of the fluorinase enzyme from Streptomyces cattleya, which has the ability to form a C-F bond with inorganic fluoride. The presentation describes the isolation and purification of the enzyme and illustrates how it can be used, in a two-enzyme reaction, to prepare [5-18F]-5-fluoro-5-deoxyribose ([18F]-FDR). The sugar [18F]-FDR emerges as an excellent ligand for bioconjugation to clinically significant peptides. Moreover, it holds promise as a new methodology for labelling peptides with the fluorine-18 isotope, for application in clinical imaging by positron emission tomography (PET).