Walter Hoppe
Encyclopedia
Walter Hoppe was a German
physicist
and electron microscopist
.
Walter Hoppe was born in Wallsee/Donau, Austria
and obtained his doctorate in chemistry at the German University in Prague
under Professor J. Boehm.
Hoppe became professor and departmental head at the Max Planck Institute of Biochemistry
in Martinsried
, Germany
from 1964 until his retirement in 1985.
His most important contributions in the 1960s to 1980s were based on his experience with X-ray diffraction and electron microscopy, from which he derived pioneering theories, including the invention of "ptychography
". These led to experimental studies of the practicability of performing high resolution three-dimensional reconstructions of complex biological macromolecules which at that time were not able to be assembled into the crystalline arrays necessary for structural determination by X-ray diffraction (e.g. ribosome
s). Hoppe's ideas of combining many images of the same specimen (a negatively-stained electron microscope preparation containing the object of interest) recorded over a wide range of tilt angles (not necessarily restricted to a simple tilt axis perpendicular to the electron beam), followed by reconstruction of the three-dimensional object via mathematical manipulations involving Fourier space transforms or weighted filtered back projections, constitute the basis of many extant 3D reconstruction techniques, including computer tomography in medicine and internal investigation of materials. He was acutely aware of electron damage causing alteration of the specimen's structure during observation and his studies contributed significantly to the development of minimal dose methodology. Much of his early contribution to the field has been overlooked by other workers since it was published mainly in German language journals. A biographical note appeared in J. Appl. Cryst. (1987). 20, 324-325 (see: http://journals.iucr.org/j/issues/1987/04/00/a27772/a27772.pdf).
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
and electron microscopist
Electron microscope
An electron microscope is a type of microscope that uses a beam of electrons to illuminate the specimen and produce a magnified image. Electron microscopes have a greater resolving power than a light-powered optical microscope, because electrons have wavelengths about 100,000 times shorter than...
.
Walter Hoppe was born in Wallsee/Donau, Austria
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
and obtained his doctorate in chemistry at the German University in Prague
Charles University in Prague
Charles University in Prague is the oldest and largest university in the Czech Republic. Founded in 1348, it was the first university in Central Europe and is also considered the earliest German university...
under Professor J. Boehm.
Hoppe became professor and departmental head at the Max Planck Institute of Biochemistry
Max Planck Institute of Biochemistry
The Max Planck Institute of Biochemistry is a research institute of the Max Planck Society located in Martinsried, a suburb of Munich. The Institute was "founded in 1973 by the merger of three formerly independent institutes: the Max Planck Institute of Biochemistry, the Max Planck Institute of...
in Martinsried
Martinsried
Martinsried is a section of Planegg, a municipality neighboring Munich, Germany. Martinsried lies about 15 km southwest of Munich's city center.Martinsried is mostly known as the location of the Max Planck Institute of Biochemistry and the...
, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
from 1964 until his retirement in 1985.
His most important contributions in the 1960s to 1980s were based on his experience with X-ray diffraction and electron microscopy, from which he derived pioneering theories, including the invention of "ptychography
Ptychography
Ptychography is a name given to a technique invented by Walter Hoppe that aims to solve the diffraction-pattern phase problem by interfering adjacent Bragg reflections coherently and thus determining their relative phase...
". These led to experimental studies of the practicability of performing high resolution three-dimensional reconstructions of complex biological macromolecules which at that time were not able to be assembled into the crystalline arrays necessary for structural determination by X-ray diffraction (e.g. ribosome
Ribosome
A ribosome is a component of cells that assembles the twenty specific amino acid molecules to form the particular protein molecule determined by the nucleotide sequence of an RNA molecule....
s). Hoppe's ideas of combining many images of the same specimen (a negatively-stained electron microscope preparation containing the object of interest) recorded over a wide range of tilt angles (not necessarily restricted to a simple tilt axis perpendicular to the electron beam), followed by reconstruction of the three-dimensional object via mathematical manipulations involving Fourier space transforms or weighted filtered back projections, constitute the basis of many extant 3D reconstruction techniques, including computer tomography in medicine and internal investigation of materials. He was acutely aware of electron damage causing alteration of the specimen's structure during observation and his studies contributed significantly to the development of minimal dose methodology. Much of his early contribution to the field has been overlooked by other workers since it was published mainly in German language journals. A biographical note appeared in J. Appl. Cryst. (1987). 20, 324-325 (see: http://journals.iucr.org/j/issues/1987/04/00/a27772/a27772.pdf).
Literature
- Hoppe, W. (1974) Towards three-dimensional “electron microscopy” at atomic resolution. Naturwissenschaften, 61, No. 6, pp. 239–249.
- Hoppe, W., Schramm, H. J., Sturm, M., Hunsmann, N., and Gaβmann, J. (1976) Three-dimensional electron microscopy of individual biological objects. I. Methods. Z. Naturforsch. 31a, pp. 645–655.
- Hoppe, W., Schramm, H. J., Sturm, M., Hunsmann, N., and Gaβmann, J. (1976) Three-dimensional electron microscopy of individual biological objects. II. Test calculations. Z. Naturforsch. 31a, p. 1370.
- Hoppe, W., Schramm, H. J., Sturm, M., Hunsmann, N., and Gaβmann, J. (1976) Three-dimensional electron microscopy of individual biological objects. III. Experimental results on yeast fatty acid synthetase. Z. Naturforsch. 31a.
- Hoppe, W. and Grill, B. (1976) Prospects of three-dimensional high resolution electron microscopy of non-periodic structures. Ultramicroscopy Vol. 2, 1976–1977, pp. 153–168.
- Radermacher, M. and Hoppe, W. (1978) 3-D reconstruction from conically tilted projections. Proceedings of the 9th International Congress on Electron Microscopy, Vol. 1, pp. 218–219.
- Hoppe W and Hegerl R. (1980) Three-dimensional structure determination by electron microscopy. In: Hawkes PW, editor. Computer Processing of Electron Microscope Images. Springer-Verlag; Heidelberg: 1980. pp. 127–186.
- Hoppe, W. (1983) Electron Diffraction with the Transmission Electron Microscope as a Phase-Determining Diffractometer—From Spatial Frequency Filtering to the Three-Dimensional Structure Analysis of Ribosomes. Angewandte Chemie International Edition in English, Volume 22, Issue 6, pages 456–485.