Tiselius’ stripes

The German language has the wonderful if quaint word ‘doctor-father’ (or increasingly doctor-mother) to refer to one’s research supervisor. By extension one’s lab mates are your doctor brothers and sisters. It is a phrase that nicely describes the relationship between a student and their mentor, a relationship that can be blissful or filled with tension. Among the former is the story of Arne Tiselius, whose entire doctor-family devoted their work to inventing tools for separating large molecules. In so doing, they transformed biological chemistry.

Tiselius, whose father died when he was four, studied chemistry at the University of Uppsala. When he graduated in 1925, he found a position as a research assistant with the most exciting scientist in Sweden, Thé Svedberg (Chemistry World, June 2019, p70). A physicist with a strong biological bent, Svedberg was convinced that the macromolecules of the cell held the key to understanding biology. He had carried out the first experiments towards separating the components of cells by ultracentrifugation. The result implied that far from being just ‘colloids’ whose nature seemed formless and diffuse, the components of cells were molecules. Big ones.