Deisenhofer, Johann (1943– )

German chemist who was the first to apply the technique of X-ray crystallography (the use of X-rays to discern atomic structure) to biological molecules. He shared the Nobel Prize for Chemistry in 1988 with Robert Huber and Harmut Michel for their determination of the three-dimensional structure of a photosynthetic reaction centre from a bacterium.

In 1982, Michel succeeded in preparing crystals of a photosynthetic reaction centre from a purple bacterium, Rhodipseudomonas viridis. During 1982–85, Deisenhofer, Huber, and Michel used X-ray crystallography to determine the atomic structure of the reaction centre in detail. This work not only increased the understanding of photosynthesis, but also has implications for the study of membrane-bound proteins (proteins within a cell membrane) that play a part in many biological processes, such as the transport of nutrients into cells.

Deisenhofer was born in Zusamaltheim, Bavaria, and educated at the Technical University at Munich and the Max Planck Institute for Biochemistry in Munich (and later Martinsried, near Munich). Working in Huber's laboratory at Martinsried, he obtained his doctorate in 1974 for the application of X-ray crystallography to biological molecules. In 1988, Deisenhofer moved to the USA and became professor of biochemistry at the University of Texas in Dallas.