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Horace A. Barker. "Exploration of Bacterial Metabolism." Annual Review of Biochemistry 47 (1978): 1-33
King-Thom Chung. "Horace A. Barker (1907) Pioneer of Anaerobic Metabolism." Anaerobe 5 (1999): 513-7.

Beijerinck, Martinus W. (1851-1931) Dutch microbiologist

Educated at the Delft Technical School and the University of Leiden (Ph.D. 1899), Beijerinck taught in agricultural schools, worked in the Netherlands Yeast and Alcohol Manufactory (1884-95), and taught at the Technical School in Delft (1895-1921). His research on the biology of gall wasps and gall formation in1882 led to the theory of ontogeny in higher plants and animals as being controlled by a series of growth enzymes that become active in fixed succession. He made major contributions to microbiology by developing the enrichment culture technique, simultaneously with Sergey Winogradsky, which permits the isolation of highly specialized microorganisms. Beijerinck cultivated and isolated Rhizobium leguminosarum, a bacillus that fixes free nitrogen and causes the formation of nodules on the roots of Leguminosae. He also characterized Azobacter as nitrogen-fixing, and isolated the new genus, Aerobacter. In studying tobacco mosaic disease, he concluded that the filterable pathogen was a contagium vivum fluidum, a term coined to convey his concept of a living infectious agent in a fluid (noncellular) form—a revolutionary idea at a time when life and cellularity were thought to be inextricably connected.

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Pieter Bos and Bert Theunissen, eds. Beijerinck and the Delft School of Microbiology. Delft: Delft University Press, 1995.

Berzelius, Jöns Jacob (1779-1848) Swedish chemist

Berzelius's early life was marked by a struggle to obtain a satisfactory education. In 1796 he entered the University of Uppsala but his studies were interrupted because of lack of funds. He began his chemical experiments without any official encouragement and from 1799 he worked during the summers as a physician at Medevi Springs where he analyzed the waters. He finally obtained his M.D. in 1802 with a dissertation on the medical uses of the voltaic pile. After graduating, Berzelius moved to Stockholm where he did research with Wilhelm Hisinger, a mining chemist. Their fist success came in 1803 with the isolation of cesium, although the discovery was anticipated by Martin Klaproth. Berzelius later discovered selenium (1817), thorium (1828), and his coworkers discovered lithium (1818) and vanadium (1830). In 1807 Berzelius was appointed professor at the School of Surgery in Stockholm (later the Karolinska Institute).

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