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H. A. Barker

  • National Medal of Science
  • Biological Sciences

For his profound study of the chemical activities of microorganisms, including the unraveling of fatty acid metabolism and the discovery of the active coenzyme form of vitamin B12.

It’s found in fish, meat and eggs. Vitamin B12 is an essential nutrient, helping our bodies make the red blood cells that transport oxygen to our organs and extremities. This knowledge is – in part – the result of one man with an affinity for soil microbiology.

In 1959, Horace A. Barker, known as “Nook” to his friends, discovered vitamin B12 coenzyme while analyzing common soil bacteria found in the San Francisco Bay’s mud. A coenzyme is a non-protein molecule that aids an enzyme – the catalyst for a biochemical reaction.

Mapping out the nutrient’s role in metabolic activity, Barker established B12’s importance in building body tissue and preventing diseases, including pernicious anemia.

Aside from his scientific accomplishments, Barker was known to his students at U.C. Berkeley as a great teacher and mentor. As a student in his laboratory once wrote, “He teaches the course the way everyone imagines their favorite grandfather would do it.”