Arne Wilhelm Kaurin Tiselius
1902-1971
Swedish Biochemist
Arne Tiselius was a Nobel Prize-winning biochemist who helped to develop techniques for separating mixtures of proteins into their individual components. These methods allowed researchers to obtain specific proteins for further study.
Arne Tiselius was born in Stockholm, Sweden, in 1902, and he became interested in chemistry during childhood. He went on to study this subject at Uppsala University. A major factor in his decision to attend this school was the presence of Theodor Svedberg (1884-1971), a well-known chemist. By 1924, Tiselius had earned his master's degree in chemistry, physics, and mathematics. He remained at the university in order to work as a research assistant to Svedberg.
Svedberg was interested in isolating individual proteins from organisms. One of the techniques he considered using was electrophoresis. In this technique, a mixture of electrically charged molecules (such as proteins) is placed in an electric field. Molecules with a negative charge move toward the positive end of the field, and vice versa. Molecules with more charge move faster than do those with less charge. In addition, smaller molecules move faster than larger molecules. As a result, electrophoresis can separate a mixture of proteins into individual bands based on the proteins' charge and size.
Tiselius began working with Svedberg on the use of electrophoresis to separate proteins called albumins. Albumins are a group of similar proteins that help to transport substances in the bloodstream. By 1930, Tiselius had earned his doctorate degree and had become an assistant professor in chemistry. At the time, the field of biochemistry—which includes the study of proteins—was not officially recognized at Uppsala University. Therefore, Tiselius decided to turn to more traditional fields of chemistry in order to become a full professor.
For several years, he studied zeolite minerals. The crystals of these minerals adsorb water; that is, they attract water to their surfaces. These crystals can also adsorb other chemicals such as ethyl alcohol, bromine, and mercury. While working with these minerals at Princeton University in the United States, Tiselius met biologists and chemists who knew of his work with Svedberg. They encouraged him to continue with his investigation into electrophoresis because they felt it would be of use to their own projects in protein research.
When Tiselius returned to Uppsala, he once again began to experiment with electrophoresis. He developed new equipment that allowed him to obtain more accurate data, and he was eventually able to separate proteins from the blood serum of horses. Serum is the liquid portion of the blood from which certain molecules have been removed. Electrophoresis separated the serum proteins into four bands. One band consisted of albumins; the other three were unknown. Tiselius named them alpha, beta, and gamma globulins. It is now known that alpha and beta globulins have several important functions such as transporting other substances and aiding in blood clotting. Gamma globulins are also known as antibodies; they play an important role in the immune system. Tiselius's work revealed the complexity of blood proteins, and as a result of this research, he was made the first professor of biochemistry at Uppsala University.
Tiselius soon realized that some biological chemicals are so similar that electrophoresis cannot separate them. In the 1940s, he began to study how adsorption chromatography could be used to isolate proteins. Adsorption chromatography relies on the fact that some chemicals adsorb, or adhere, more strongly to certain materials than do other chemicals. Tiselius developed a method of adsorption chromatography that involves a column packed with zeolite crystals, which act as an adsorbent. When a mixture of proteins is poured into the column, the proteins least attracted to the zeolite crystals pass through the bottom of the column first, and those mostattracted to the crystals pass through the column last. Tiselius and Frederick Sanger (1918-1982) used this technique to separate the hormone insulin into its four components.
In 1948, Tiselius was awarded the Nobel Prize for Chemistry for his work on the separation of proteins using electrophoresis and adsorption chromatography. Between 1960 and 1964, he served as president of the Nobel Foundation. He received 11 honorary degrees from various universities and won numerous other awards.
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