Frederik Hopkins

Frederik Hopkins

English biochemist who discovered growth-stimulating vitamins (A and D). In 1929 he was awarded the Nobel Prize.
Date of Birth: 20.06.1861
Country: Great Britain

Biography of Frederick Gowland Hopkins

Frederick Gowland Hopkins was an English biochemist who discovered vitamins A and D, which stimulate growth. He was awarded the Nobel Prize in 1929. Hopkins was born in Eastbourne, East Sussex, to Elizabeth (Gowland) and Frederick Hopkins. His cousin, Gerard Manley Hopkins, was a poet.

From a young age, Hopkins had a passion for science and spent much of his time reading Dickens and writing poetry. At the age of 8, he was allowed to use his father's microscope to study organisms he caught in the sea. This sparked his interest in science even more, although there was no one around to explain what he was seeing. In 1871, his mother moved to Enfield, a rural area near London, to live with her mother and brother, and Hopkins was sent to a London city school. Despite excelling in chemistry and English, he preferred visiting museums and libraries over attending school. He was eventually sent to a private school with a three-year curriculum.

When Hopkins turned 17, his family believed his education was complete and found him a job as an insurance clerk. However, shortly after finishing school, he wrote an article about the purple smoke emitted by bombardier beetles, which was accepted for publication in "The Entomologist" journal. He later stated, "Since then I have been a biochemist at heart." Over the next three years, he studied analytical chemistry at a pharmaceutical company. With a small inheritance from his grandfather, Hopkins was able to study chemistry first at the Royal School of South Kensington and then at University College London. His high score on the chemistry exam allowed him to become an assistant to Sir Thomas Stevenson, an expert in toxicology and forensic medicine at Guy's Hospital. Working with Stevenson, whom he considered a "born and remarkable leader," Hopkins obtained a Bachelor of Science degree at the University of London.

Upon recommendation from Stevenson, Hopkins was admitted to the medical school at Guy's with a Gulstonian scholarship for research in 1888. At Guy's, Hopkins continued his laboratory experiments in chemistry. In 1891, he published a description of the precipitation of uric acid using ammonium chloride, an analytical method that was used for many years. He also demonstrated that uric acid was a component of the white pigment found in certain butterflies, which was a result of his lifelong curiosity about all insects. His last publication focused on insect pigmentation.

After receiving his medical degree from Guy's in 1894, Hopkins remained at the school for another four years as a lecturer in physiology, chemistry, toxicology, and physics. During the last two years, he led the clinical research department, where laboratory investigations were conducted for diagnostic and therapeutic purposes. In his protein chemistry experiments, Hopkins developed methods for isolating proteins from blood and egg white, as well as methods for crystallizing proteins in large quantities for further research.

In 1898, Hopkins was invited by Michael Foster to the University of Cambridge as a researcher and lecturer in chemical physiology, now known as biochemistry. Foster, a highly influential scientist and teacher, supported Hopkins' desire to work in this field. The position at Cambridge was poorly paid, so Hopkins supplemented his income by tutoring medical students at Emmanuel College, where he was a fellow and lecturer in 1906.

While teaching at Cambridge, Hopkins' regular experiments with proteins led him to discover the amino acid tryptophan. When a protein tested by one of his students did not turn blue in the standard Adamkiewicz color test, Hopkins suspected that analyzing this color reaction could provide new insights into protein structure. He isolated and identified tryptophan, adding it to the growing list of amino acids (protein building blocks) discovered by Emil Fischer, Albrecht Kossel, and other researchers. In 1906, Hopkins showed that different proteins fed to mice had different effects on growth, particularly that proteins lacking tryptophan were insufficient for the body's needs. He concluded that the properties of proteins depended on the types of amino acids present in them. Believing that protein properties were determined by an adequate diet, he fed mice a diet consisting of lard, starch, and casein (milk protein). When the animals stopped growing, he added a small amount of milk containing the missing factors necessary for growth. These "accessory food factors," as he called them, were later named vitamins by the Polish chemist Casimir Funk. In 1910, Hopkins briefly interrupted his work due to reduced productivity caused by exhaustion. In 1912, he published his research results in the article "Feeding Experiments Illustrating the Importance of Accessory Factors in Normal Dietaries." While Hopkins considered his vitamin research secondary to his studies of intermediary metabolism, a complex series of oxidation and reduction reactions by which cells obtain energy, he demonstrated that intermediary metabolism involved ordinary chemical reactions. By showing that lactate accumulates in muscles when oxygen levels decrease, he and his colleague Walter Fletcher laid the groundwork for the discovery of the use of carbohydrate metabolism for muscle contraction by Archibald V. Hill and Otto Meyerhof. In 1921, Hopkins isolated glutathione, a tripeptide formed by three amino acids, which he named and identified as necessary for oxygen transport in plant and animal cells. He also discovered xanthine oxidase, an enzyme that catalyzes the oxidation of xanthine and hypoxanthine (colorless crystalline substances) to uric acid.

One of Hopkins' most valuable qualities was his ability as a scientific pioneer, to identify key controversial issues and generate interest in them among other researchers. In 1914, he was appointed head of the Department of Biochemistry at Cambridge. In 1925, he moved to the newly built Sir William Dunn School of Pathology. In 1929, Hopkins shared the Nobel Prize in Physiology or Medicine with Christiaan Eijkman "for the discovery of vitamins, stimulating growth processes." In his Nobel Lecture, "The Earlier History of Vitamin Research," Hopkins reminded his audience that his 1912 article had noted the existence of "essential food substances, not seriously considered as a subject of physiological necessity." While acknowledging Casimir Funk for his contributions to the study of vitamins, Hopkins noted that he was "the first to realize the true significance of the facts revealed."

From 1930 to 1935, Hopkins served as President of the Royal Society, which allowed him to continue his research. After 1935, he continued his experiments on insect pigments and intermediary metabolism, even as his vision deteriorated and his health declined. In 1898, Hopkins married Jessie Anne Stevens, and they had a son who became a doctor and two daughters, one of whom became a biochemist. His colleague Henry H. Dale described Hopkins as "a man of frail build and delicate health... His face was usually thoughtful, grave, but quickly lighted with genuine attention, humor, or a desire to share his companion's difficulties." He passed away in Cambridge on May 16, 1947.

In 1925, Hopkins was knighted, and in 1935, he was awarded the Order of Merit. His numerous awards included the Royal Medal in 1918 and the Copley Medal of the Royal Society in 1926.