Melvin Calvin

Melvin Calvin (1962)

Melvin Calvin (born April 8, 1911 in Saint Paul , Minnesota , † January 8, 1997 in Berkeley , California ) was an American chemist, biochemist and Nobel Prize winner who succeeded after the Second World War to elucidate the secondary reaction of photosynthesis .

The discovery of the Calvin cycle

Together with his working group at the University of California at Berkeley , he determined how plants fix CO ₂ and which biochemical reactions take place. To clarify these processes he used the marking of molecules with radioactive atoms.

First, Calvin put green algae of the genus Chlorella and Scenedesmus into a solution containing the radioactive isotope of carbon [ ], the radiation , in the form of carbon dioxide [emits contained]. The algae were illuminated and photosynthesized, during which they recorded. After the exposure time, they were killed in hot alcohol and their cellular constituents were removed. These substances were then separated by paper chromatography . Since the substances sought by Calvin were colorless, he placed his chromatogram on an X-ray film that was colored black by ionizing radiation from the carbon isotope. A comparison chromatography was carried out to identify the substances. If a known and an unknown substance occupy the same position in the chromatogram, it is assumed that these substances are identical. ${\ displaystyle ^ {14} \ mathrm {C}}$ ${\ displaystyle \ beta}$ ${\ displaystyle ^ {14} \ mathrm {CO} _ {2}}$ ${\ displaystyle ^ {14} \ mathrm {CO} _ {2}}$

After Calvin found twelve different chemical compounds, he set out to find out the order in which they were synthesized.

He added a solution with radioactive carbon dioxide again, but exposed his algae for different lengths of time. After a few seconds of exposure, only a single radioactive substance was formed: glyceric acid phosphate (a molecule with three carbon atoms; body). ${\ displaystyle \ mathrm {C} _ {3}}$

The further sequence of the substances and their structural formulas can be found under the Calvin cycle .

The last reaction product was ribulose biphosphate (also known as ribulose bisphosphate or ribulose diphosphate , a molecule with five carbon atoms; body). ${\ displaystyle \ mathrm {C} _ {5}}$

If this body combines with a molecule, a body is created which, due to its instability, disintegrates into two bodies, which were the first to be detected as radioactive substances. ${\ displaystyle \ mathrm {C} _ {5}}$ ${\ displaystyle \ mathrm {CO} _ {2}}$ ${\ displaystyle \ mathrm {C} _ {6}}$ ${\ displaystyle \ mathrm {C} _ {3}}$

Calvin concluded from the results of his experiments that it had to be a circular process, which was later named in his honor the "Calvin cycle". In 1954 he was elected to the National Academy of Sciences , 1958 to the American Academy of Arts and Sciences and the Royal Dutch Academy of Sciences (KNAW), in 1959 a member of the Leopoldina and 1960 a member of the American Philosophical Society . In 1959 he was elected a foreign member of the Royal Society of London and in 1963 an honorary member ( Honorary Fellow ) of the Royal Society of Edinburgh . In 1961 he finally received the Nobel Prize in Chemistry for his work .

In November 1961 Melvin Calvin was a participant in the first SETI conference at the Green Bank Observatory .

Private

His parents were Russian Jews. In 1942 he married Genevieve Jemtegaard. They had two daughters together, Elin and Karole, and a son, Noel.

literature

Melvin Calvin: Following the trail of light: a scientific Odyssey. American Chemical Society, Washington 1992, ISBN 0-8412-1829-3 .
Melvin Calvin: Chemical evolution: molecular evolution towards the origin of living systems on the earth and elsewhere. Clarendon Press, Oxford 1969.

Web links

Commons : Melvin Calvin - Collection of images, videos and audio files

Information from the Nobel Foundation on the 1961 award ceremony for Melvin Calvin (English)
Melvin Calvin, Who Unraveled the Secrets of Photosynthesis, Dies
Melvin Calvin Dies at 85; Biochemist Won Nobel Prize. In: The New York Times . January 10, 1997 (obituary)
Biographical Memoirs ( November 1, 2013 memento on the Internet Archive ), The National Academies Press

Individual evidence

↑ Died: Melvin Calvin Der Spiegel, January 13, 1997.

^ JA Bassham, SA Barker, M. Calvin, UC Quarck: Intermediates in the photosynthetic cycle . In: Biochimica et Biophysica Acta . tape 21 , no. 2 , August 1956, p. 376-377 , doi : 10.1016 / 0006-3002 (56) 90022-1 .

↑ Sebastian von Hoerner : Are we alone? - SETI and life in space. Beck, Munich 2003, ISBN 3-406-49431-5 , pp. 151-152.

↑ Green Bank conference (1961) ( Memento of the original from May 18, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. , daviddarling.info @1@ 2

^ Biography nobelprize.org

personal data
SURNAME	Calvin, Melvin
BRIEF DESCRIPTION	American chemist and biochemist
DATE OF BIRTH	April 8, 1911
PLACE OF BIRTH	Saint Paul , Minnesota
DATE OF DEATH	January 8, 1997
Place of death	Berkeley , California

[1] Died: Melvin Calvin Der Spiegel, January 13, 1997.

[2] JA Bassham, SA Barker, M. Calvin, UC Quarck: Intermediates in the photosynthetic cycle . In: Biochimica et Biophysica Acta . tape 21 , no. 2 , August 1956, p. 376-377 , doi : 10.1016 / 0006-3002 (56) 90022-1 .

[3] Sebastian von Hoerner : Are we alone? - SETI and life in space. Beck, Munich 2003, ISBN 3-406-49431-5 , pp. 151-152.