The Origin of the Word Protein *

The word protein first appeared in scientific literature in 1838. It was used by Mulder as the designation of the complex radical which he thought to be combined with sulfur and phosphorus in the proteins as they occur in nature, and it has been commonly assumed that he himself originated the new term. That this is incorrect has recently been pointed out by Sir Harold Hartley"' who, in the course of preparing an address commemorating the centenary of the death of Berzelius, found that Berzelius had suggested the word protein to Mulder in a letter written from Stockholm on July 10, 1838.' Inasmuch as the correct origin of this word has been almost universally overlooked, the sequence of events which led to its publication may be of interest. Mulder's investigations of proteins were begun in 1835 with chemical analyses of silk' and were soon extended to include fibrin, serum and egg albumin, gelatin, and a preparation of what is today known as wheat glutenin, together with various products derived from these substances by the action of acids and alkalies. Certain apparent regularities in the ultimate composition of the preparations convinced him of the presence in each of them of what contemporary chemical theory regarded as an oxidized basic radical which combined in simple ratios with sulfur and phosphorus to give the substances as they are found in nature. The name "protein," derived from the Greek adjective Wipw7qxo , meaning of the first rank or position, was given to this radical. Mulder was convinced of the importance of these results and took what today seem rather extreme steps to provide for their wide dissemination. Two papers were published in journals of which he was himself an editor. In one of these, Natuuren scheikundig Archief, his accounte appears in volume 6 under the title "Over Proteine en hare Verbindingen en Ontledingsproducten" and runs from pages 87 to 162. A briefer article was