What are the sources of avidin?
                                
                                
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                                    3 min read                                
                            
                                The powerful, non-covalent bond between avidin and the vitamin biotin is one of the strongest in nature, with a dissociation constant of approximately 10⁻¹⁵ M. A primary source of avidin is the egg whites of birds, reptiles, and amphibians, where its function is to sequester biotin.