Poppea’s bath liquor: the secret proteome of she-donkey’s milk

Donkey's milk is today categorized among the best mother's milk substitute for allergicnewborns, due to its much reduced or absent allergenicity, coupled to excellent palatabilityand nutritional value. However, up to the present, only a handful of proteins had beencharacterized, just about the standard eight to ten major ones known in all types of milk. Byexploiting the combinatorial peptide ligand library technology, and treating large volumes(up to 300 mL) of defatted, de-caseinized (whey) milk, we have been able to identify 106unique gene products, by far the largest description so far of this precious nutrient. Due topoor knowledge of the donkey's genetic asset, only 10% of the proteins could be identified byconsulting the data base of Equus asinus; the largest proportion (70%) could be identified byhomology with the proteins of Equus caballus.