Christoph Cremer
Encyclopedia
Christoph Cremer is a German physicist and professor at the Ruprecht-Karls-University Heidelberg
, who has successfully overcome the conventional limit of resolution that applies to light based investigations (the Abbe limit) by a range of different methods (1971/1978 development of the concept of 4Pi-microscopy; 1996 localization microscopy
SPDM; 1997 spatially structured illumination SMI).
His actual microscope Vertico-SMI is the world’s fastest nano light microscope that allows large scale investigation of supramolecular complexes including living cell conditions. It allows 3 D imaging of biological preparations marked with conventional fluorescent dyes and reaches a resolution of 10 nm in 2D and 40 nm in 3D.
This nanoscope has therefore the potential to add substantially to the current revolution in optical imaging which will affect the entire molecular biology, medical and pharmaceutical research. The technology allows the development of new strategies for the prevention, the lowering of risk and therapeutic treatment of diseases.
and history
at Freiburg University and Munich University, Christoph Cremer studied Physics in Munich
(with financial support from the "Studienstiftung des Deutschen Volkes") and completed his doctoral studies (Dr. rer.nat.) in Genetics
and Biophysics
in Freiburg. This was followed by post-doctoral studies at the Institute for Human Genetics
at Freiburg University, several years in the USA at the University of California
, and his „Habilitation“ (Dr. med. habil. in General Human Genetics and Experimental Cytogenetics, Medical Faculty, Freiburg University). Since 1983, he is teaching as a professor (chair since 2004) for “applied optics and information processing” at the Kirchhoff Institute for Physics at the University of Heidelberg. In addition, he is a scientific member of the Interdisciplinary Center for Scientific Computing
(IWR), of the Institute for Pharmacy and Molecular Biotechnology (IPMB), as well as of the University’s „Bioquant“ Center. Christoph Cremer is a participant in three current “Projects of Excellence” of the University of Heidelberg (2007–2012), and is also a partner in the Biotechnology Cluster for cell-based and molecular medicine, one of five clusters selected in 2008 as German BMBF Clusters of Excellence. Elected as Second Speaker of the Senate of the University of Heidelberg (since 2006), Professor Cremer is also involved in university governance and politics. In his function as Adjunct Professor at the US University of Maine
and as scientific member of the renowned Jackson Laboratory
(Bar Harbor/Maine), where he undertakes research for several weeks each year during the semester breaks, he is involved in the establishment of the biophysics center (Institute for Molecular Biophysics, IMB). IMB is linked with the University of Heidelberg through a „Global Network“ collaboration . He is married to architect
and artist Dr. Letizia Mancino-Cremer, who since 1992 is president of the Goethe-Gesellschaft Heidelberg (www.letizia-mancino.eu).
based light microscopy approaches. First ideas had their origin in his graduate student years in the 1970s. Jointly with his brother Thomas Cremer
, now professor (chair) of Anthropology and Human Genetics at the Ludwigs-Maximilian University in Munich, Christoph Cremer proposed in a patent application in 1971 (DE 2116521) on the development of a hologram-based laser scanning 4Pi microscope
. This patent
application already contains the first ideas about the use of light switchable molecules for the improved optical acquisition of nanostructural information. The basic idea was to focus laser light from all sides (space angle 4Pi) in a spot with a diameter smaller than the conventional laser focus and to scan the object by means of this spot. In this manner, it should be possible to achieve an improved optical resolution
beyond the conventional limit (approx. 200 nm lateral, 600 nm axial. Since 1992, 4Pi microscopy has been developed by Stefan Hell (currently director at the Max-Planck Institute for Biophysical Chemistry, Göttingen, Germany) into a highly efficient, high resolution imaging process, using two microscope objective lenses of high numeric aperture opposing each other.
laser micro irradiation instrument which for the first time made it possible to irradiate in a controlled manner only a tiny part of a living cell at the absorption maximum for DNA
(257 nm). This replaced the conventional UV partial irradiation practiced for over 60 years. In this way, it was possible for the first time to induce alterations in the DNA in a focused manner (i.e. at predetermined places in the cell nucleus
of living cells) without compromising the cells ability to divide and to survive. Specific very small cell regions could be irradiated and thus the dynamics of macromolecules (DNA) contained there quantitatively estimated. Furthermore, due to the high speed of the process using irradiation times of fractions of a second, it became possible to irradiate even moving cell organelles. This development provided the basis for important experiments in the area of genome
structure research (establishing the existence of so-called chromosome
territories in living mammalian cells) and led, a few years later (1979/1980) to a successful collaboration with the biologist Christiane Nüsslein-Volhard
(currently Director at the Max Planck Institute for Developmental Biology
, Tübingen
, Germany; Nobel Prize
1995). In this collaboration Christoph Cremer used his UV laser micro irradiation equipment to elicit cellular changes in the early larval stages of the fruit fly Drosophila melanogaster
.
(EMBL) in Heidelberg and their industry partners. In later years, this technology was adopted widely by biomolecular and biomedical laboratories and remains to this day the gold standard as far as three dimensional light microscopy with conventional resolution is concerned.
limit of approximately 200 nm (lateral).
Around 1995, Christoph Cremer commenced with the development of a light microscopic process, which achieved a substantially improved size resolution of cellular nanostructure
s stained with a fluorescent marker. This time he employed the principle of wide field microscopy combined with structured laser illumination (spatially modulated illumination, SMI. Currently, a size resolution of 30 – 40 nm (approximately 1/16 – 1/13 of the wave length used) is being achieved. In addition, this technology is no longer subjected to the speed limitations of the focusing microscopy so that it becomes possible to undertake 3D analyses of whole cells within short observation times (at the moment around a few seconds).
Also since around 1995, Christoph Cremer developed and realized new fluorescence based wide field microscopy approaches which had as their goal the improvement of the effective optical resolution (in terms of the smallest detectable distance between two localized objects) down to a fraction of the conventional resolution (spectral precision distance/position determination microscopy, SPDM). Combining SPDM and SMI, known as Vertico SMI
microscopy Christoph Cremer can currently achieve a resolution of approx. 10 nm in 2D and 40 nm in 3D in wide field images of whole living cells. Widefield 3D “nanoimages” of whole living cells currently still take about two minutes, but work to reduce this further is currently under way. Vertico-SMI is currently the fastest optical 3D nanoscope for the three dimensional structural analysis of whole cells worldwide.
With this optical nanoscope, it is possible to use conventional, well established and inexpensive fluorescent dyes, from the GFP
group, subject of a Nobel Prize
in 2008, and its dye variants, to the well-known Alexa and fluorescein dyes.
Heidelberg
-Early history:Between 600,000 and 200,000 years ago, "Heidelberg Man" died at nearby Mauer. His jaw bone was discovered in 1907; with scientific dating, his remains were determined to be the earliest evidence of human life in Europe. In the 5th century BC, a Celtic fortress of refuge and place of...
, who has successfully overcome the conventional limit of resolution that applies to light based investigations (the Abbe limit) by a range of different methods (1971/1978 development of the concept of 4Pi-microscopy; 1996 localization microscopy
Microscopy
Microscopy is the technical field of using microscopes to view samples and objects that cannot be seen with the unaided eye...
SPDM; 1997 spatially structured illumination SMI).
His actual microscope Vertico-SMI is the world’s fastest nano light microscope that allows large scale investigation of supramolecular complexes including living cell conditions. It allows 3 D imaging of biological preparations marked with conventional fluorescent dyes and reaches a resolution of 10 nm in 2D and 40 nm in 3D.
This nanoscope has therefore the potential to add substantially to the current revolution in optical imaging which will affect the entire molecular biology, medical and pharmaceutical research. The technology allows the development of new strategies for the prevention, the lowering of risk and therapeutic treatment of diseases.
Biography
Following a few semesters studying philosophyPhilosophy
Philosophy is the study of general and fundamental problems, such as those connected with existence, knowledge, values, reason, mind, and language. Philosophy is distinguished from other ways of addressing such problems by its critical, generally systematic approach and its reliance on rational...
and history
History
History is the discovery, collection, organization, and presentation of information about past events. History can also mean the period of time after writing was invented. Scholars who write about history are called historians...
at Freiburg University and Munich University, Christoph Cremer studied Physics in Munich
Munich
Munich The city's motto is "" . Before 2006, it was "Weltstadt mit Herz" . Its native name, , is derived from the Old High German Munichen, meaning "by the monks' place". The city's name derives from the monks of the Benedictine order who founded the city; hence the monk depicted on the city's coat...
(with financial support from the "Studienstiftung des Deutschen Volkes") and completed his doctoral studies (Dr. rer.nat.) in Genetics
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
and Biophysics
Biophysics
Biophysics is an interdisciplinary science that uses the methods of physical science to study biological systems. Studies included under the branches of biophysics span all levels of biological organization, from the molecular scale to whole organisms and ecosystems...
in Freiburg. This was followed by post-doctoral studies at the Institute for Human Genetics
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
at Freiburg University, several years in the USA at the University of California
University of California
The University of California is a public university system in the U.S. state of California. Under the California Master Plan for Higher Education, the University of California is a part of the state's three-tier public higher education system, which also includes the California State University...
, and his „Habilitation“ (Dr. med. habil. in General Human Genetics and Experimental Cytogenetics, Medical Faculty, Freiburg University). Since 1983, he is teaching as a professor (chair since 2004) for “applied optics and information processing” at the Kirchhoff Institute for Physics at the University of Heidelberg. In addition, he is a scientific member of the Interdisciplinary Center for Scientific Computing
Interdisciplinary Center for Scientific Computing
thumb|right|200px|South west view of the IWR building, located at Heidelberg's New CampusThe Interdisciplinary Center for Scientific Computing is a scientific research institute of the University of Heidelberg, Germany...
(IWR), of the Institute for Pharmacy and Molecular Biotechnology (IPMB), as well as of the University’s „Bioquant“ Center. Christoph Cremer is a participant in three current “Projects of Excellence” of the University of Heidelberg (2007–2012), and is also a partner in the Biotechnology Cluster for cell-based and molecular medicine, one of five clusters selected in 2008 as German BMBF Clusters of Excellence. Elected as Second Speaker of the Senate of the University of Heidelberg (since 2006), Professor Cremer is also involved in university governance and politics. In his function as Adjunct Professor at the US University of Maine
University of Maine
The University of Maine is a public research university located in Orono, Maine, United States. The university was established in 1865 as a land grant college and is referred to as the flagship university of the University of Maine System...
and as scientific member of the renowned Jackson Laboratory
Jackson Laboratory
The Jackson Laboratory was founded in Bar Harbor, Maine in 1929 by former University of Maine and University of Michigan president C. C. Little under the name Roscoe B...
(Bar Harbor/Maine), where he undertakes research for several weeks each year during the semester breaks, he is involved in the establishment of the biophysics center (Institute for Molecular Biophysics, IMB). IMB is linked with the University of Heidelberg through a „Global Network“ collaboration . He is married to architect
Architect
An architect is a person trained in the planning, design and oversight of the construction of buildings. To practice architecture means to offer or render services in connection with the design and construction of a building, or group of buildings and the space within the site surrounding the...
and artist Dr. Letizia Mancino-Cremer, who since 1992 is president of the Goethe-Gesellschaft Heidelberg (www.letizia-mancino.eu).
Developing the Concept of 4Pi Microscopy
Cremer was involved early in the further development of laserLaser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...
based light microscopy approaches. First ideas had their origin in his graduate student years in the 1970s. Jointly with his brother Thomas Cremer
Thomas Cremer
Thomas Cremer , is a German professor of human genetics and anthropology with a main research focus on molecular cytogenetics and 3D/4D analyses of nuclear structure studied by confocal microscopy and live cell imaging...
, now professor (chair) of Anthropology and Human Genetics at the Ludwigs-Maximilian University in Munich, Christoph Cremer proposed in a patent application in 1971 (DE 2116521) on the development of a hologram-based laser scanning 4Pi microscope
Microscope
A microscope is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy...
. This patent
Patent
A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....
application already contains the first ideas about the use of light switchable molecules for the improved optical acquisition of nanostructural information. The basic idea was to focus laser light from all sides (space angle 4Pi) in a spot with a diameter smaller than the conventional laser focus and to scan the object by means of this spot. In this manner, it should be possible to achieve an improved optical resolution
Optical resolution
Optical resolution describes the ability of an imaging system to resolve detail in the object that is being imaged.An imaging system may have many individual components including a lens and recording and display components...
beyond the conventional limit (approx. 200 nm lateral, 600 nm axial. Since 1992, 4Pi microscopy has been developed by Stefan Hell (currently director at the Max-Planck Institute for Biophysical Chemistry, Göttingen, Germany) into a highly efficient, high resolution imaging process, using two microscope objective lenses of high numeric aperture opposing each other.
Development of the first DNA Laser-UV-Microirradiation Technique for Living Cells
In the early 1970s, the brothers realized a UVUltraviolet
Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...
laser micro irradiation instrument which for the first time made it possible to irradiate in a controlled manner only a tiny part of a living cell at the absorption maximum for DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
(257 nm). This replaced the conventional UV partial irradiation practiced for over 60 years. In this way, it was possible for the first time to induce alterations in the DNA in a focused manner (i.e. at predetermined places in the cell nucleus
Cell nucleus
In cell biology, the nucleus is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these...
of living cells) without compromising the cells ability to divide and to survive. Specific very small cell regions could be irradiated and thus the dynamics of macromolecules (DNA) contained there quantitatively estimated. Furthermore, due to the high speed of the process using irradiation times of fractions of a second, it became possible to irradiate even moving cell organelles. This development provided the basis for important experiments in the area of genome
Genome
In modern molecular biology and genetics, the genome is the entirety of an organism's hereditary information. It is encoded either in DNA or, for many types of virus, in RNA. The genome includes both the genes and the non-coding sequences of the DNA/RNA....
structure research (establishing the existence of so-called chromosome
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
territories in living mammalian cells) and led, a few years later (1979/1980) to a successful collaboration with the biologist Christiane Nüsslein-Volhard
Christiane Nüsslein-Volhard
Christiane Nüsslein-Volhard is a German biologist who won the Albert Lasker Award for Basic Medical Research in 1991 and the Nobel Prize in Physiology or Medicine in 1995, together with Eric Wieschaus and Edward B...
(currently Director at the Max Planck Institute for Developmental Biology
Max Planck Institute for Developmental Biology
The Max Planck Institute for Developmental Biology is located in Tübingen, Germany. The main topics of scientific research conducted by the Max Planck Institute for Developmental Biology focus on the molecular mechanisms underlying spatial information within the embryo, communication between cells...
, Tübingen
Tübingen
Tübingen is a traditional university town in central Baden-Württemberg, Germany. It is situated south of the state capital, Stuttgart, on a ridge between the Neckar and Ammer rivers.-Geography:...
, Germany; Nobel Prize
Nobel Prize
The Nobel Prizes are annual international awards bestowed by Scandinavian committees in recognition of cultural and scientific advances. The will of the Swedish chemist Alfred Nobel, the inventor of dynamite, established the prizes in 1895...
1995). In this collaboration Christoph Cremer used his UV laser micro irradiation equipment to elicit cellular changes in the early larval stages of the fruit fly Drosophila melanogaster
Drosophila melanogaster
Drosophila melanogaster is a species of Diptera, or the order of flies, in the family Drosophilidae. The species is known generally as the common fruit fly or vinegar fly. Starting from Charles W...
.
Development of the Confocal Laser Scanning Microscopy for Fluorescence
On the basis of experience gained in the construction and application of the UV laser micro irradiation instrument, the Cremer brothers designed in 1978 a laser scanning process which scans point-by-point the three dimensional surface of an object by means of a focused laser beam and creates the over-all picture by electronic means similar to those used in scanning electron microscopes. It is this plan for the construction of a confocal laser scanning microscope (CSLM), which for the first time combined the laser scanning method with the 3D detection of biological objects labeled with fluorescent markers that earned Christoph Cremer his professorial position at the University of Heidelberg. During the next decade, the confocal fluorescence microscopy was developed into a technically fully matured state in particular by groups working at the University of Amsterdam and the European Molecular Biology LaboratoryEuropean Molecular Biology Laboratory
The European Molecular Biology Laboratory is a molecular biology research institution supported by 20 European countries and Australia as associate member state. EMBL was created in 1974 and is an intergovernmental organisation funded by public research money from its member states...
(EMBL) in Heidelberg and their industry partners. In later years, this technology was adopted widely by biomolecular and biomedical laboratories and remains to this day the gold standard as far as three dimensional light microscopy with conventional resolution is concerned.
Development of the Localization Microscopy/Spatially Structured Illumination
The goal of microscopy is in many cases to determine the size of individual, small objects. Conventional fluorescence microscopy can only establish sizes to around the conventional optical resolutionOptical resolution
Optical resolution describes the ability of an imaging system to resolve detail in the object that is being imaged.An imaging system may have many individual components including a lens and recording and display components...
limit of approximately 200 nm (lateral).
Around 1995, Christoph Cremer commenced with the development of a light microscopic process, which achieved a substantially improved size resolution of cellular nanostructure
Nanostructure
A nanostructure is an object of intermediate size between molecular and microscopic structures.In describing nanostructures it is necessary to differentiate between the number of dimensions on the nanoscale. Nanotextured surfaces have one dimension on the nanoscale, i.e., only the thickness of the...
s stained with a fluorescent marker. This time he employed the principle of wide field microscopy combined with structured laser illumination (spatially modulated illumination, SMI. Currently, a size resolution of 30 – 40 nm (approximately 1/16 – 1/13 of the wave length used) is being achieved. In addition, this technology is no longer subjected to the speed limitations of the focusing microscopy so that it becomes possible to undertake 3D analyses of whole cells within short observation times (at the moment around a few seconds).
Also since around 1995, Christoph Cremer developed and realized new fluorescence based wide field microscopy approaches which had as their goal the improvement of the effective optical resolution (in terms of the smallest detectable distance between two localized objects) down to a fraction of the conventional resolution (spectral precision distance/position determination microscopy, SPDM). Combining SPDM and SMI, known as Vertico SMI
Vertico SMI
Vertico-SMI is currently the fastest light microscope for the 3D analysis of complete cells in the nanometer range. It is based on two technologies developed in 1996, SMI and SPDM...
microscopy Christoph Cremer can currently achieve a resolution of approx. 10 nm in 2D and 40 nm in 3D in wide field images of whole living cells. Widefield 3D “nanoimages” of whole living cells currently still take about two minutes, but work to reduce this further is currently under way. Vertico-SMI is currently the fastest optical 3D nanoscope for the three dimensional structural analysis of whole cells worldwide.
With this optical nanoscope, it is possible to use conventional, well established and inexpensive fluorescent dyes, from the GFP
Green fluorescent protein
The green fluorescent protein is a protein composed of 238 amino acid residues that exhibits bright green fluorescence when exposed to blue light. Although many other marine organisms have similar green fluorescent proteins, GFP traditionally refers to the protein first isolated from the...
group, subject of a Nobel Prize
Nobel Prize
The Nobel Prizes are annual international awards bestowed by Scandinavian committees in recognition of cultural and scientific advances. The will of the Swedish chemist Alfred Nobel, the inventor of dynamite, established the prizes in 1895...
in 2008, and its dye variants, to the well-known Alexa and fluorescein dyes.
External links
- GFP Superresolution
- World of Photonics interviewing Christoph Cremer
- Christoph Cremer's Homepage
- Springer Link: European Biophysics Journal, festschrift entitled “Uncovering cellular sub-structures by light microscopy” in honour of Professor Cremer’s 65th birthday
- Christoph Cremer at the University of Maine
- Pushing the limits: single molecule imaging (PDF; 160 KB)
- University of Heidelberg, press release about the nanoscopic investigation of cellular complexes with conventional fluorescent dyes
- University of Heidelberg, press release about the world fastest nano light microscope
- Basic design of a confocal laser scanning fluorescence microscope & principle of a confocal laser scanning 4Pi fluorescence microscope, 1978
- Publication of the 4Pi DE patent application no. 2116521, 1971
- Publication list of Christoph Cremer
- Letizia Mancino's homepage