Cobalt is essential to the metabolism of all animals. It is a key constituent of cobalamin, also known as vitamin B12, the primary biological reservoir of cobalt as an ultratrace element.[1][2] Bacteria in the stomachs of ruminant animals convert cobalt salts into vitamin B12, a compound which can only be produced by bacteria or archaea. A minimal presence of cobalt in soils therefore markedly improves the health of grazing animals, and an uptake of 0.20 mg/kg a day is recommended because they have no other source of vitamin B12.[3]
Proteins based on cobalamin use corrin to hold the cobalt. Coenzyme B12 features a reactive C-Co bond that participates in the reactions.[4] In humans, B12 has two types of alkyl ligand: methyl and adenosyl. MeB12 promotes methyl (−CH3) group transfers. The adenosyl version of B12 catalyzes rearrangements in which a hydrogen atom is directly transferred between two adjacent atoms with concomitant exchange of the second substituent, X, which may be a carbon atom with substituents, an oxygen atom of an alcohol, or an amine. Methylmalonyl coenzyme A mutase (MUT) converts MMl-CoA to Su-CoA, an important step in the extraction of energy from proteins and fats.[5]
Although far less common than other metalloproteins (e.g. those of zinc and iron), other cobaltoproteins are known besides B12. These proteins include methionine aminopeptidase 2, an enzyme that occurs in humans and other mammals that does not use the corrin ring of B12, but binds cobalt directly. Another non-corrin cobalt enzyme is nitrile hydratase, an enzyme in bacteria that metabolizes nitriles.[6]
^Yamada, Kazuhiro (2013). "Chapter 9. Cobalt: Its Role in Health and Disease". In Astrid Sigel; Helmut Sigel; Roland K. O. Sigel (eds.). Interrelations between Essential Metal Ions and Human Diseases. Metal Ions in Life Sciences. Vol. 13. Springer. pp. 295–320. doi:10.1007/978-94-007-7500-8_9. ISBN 978-94-007-7499-5. PMID 24470095.
^Cracan, Valentin; Banerjee, Ruma (2013). "Chapter 10 Cobalt and Corrinoid Transport and Biochemistry". In Banci, Lucia (ed.). Metallomics and the Cell. Metal Ions in Life Sciences. Vol. 12. Springer. pp. 333–374. doi:10.1007/978-94-007-5561-1_10. ISBN 978-94-007-5560-4. PMID 23595677. electronic-book ISBN 978-94-007-5561-1 ISSN 1559-0836 electronic-ISSN 1868-0402.
^Schwarz, F. J.; Kirchgessner, M.; Stangl, G. I. (2000). "Cobalt requirement of beef cattle – feed intake and growth at different levels of cobalt supply". Journal of Animal Physiology and Animal Nutrition. 83 (3): 121–131. doi:10.1046/j.1439-0396.2000.00258.x.
^Voet, Judith G.; Voet, Donald (1995). Biochemistry. New York: J. Wiley & Sons. p. 675. ISBN 0-471-58651-X. OCLC 31819701.
^Smith, David M.; Golding, Bernard T.; Radom, Leo (1999). "Understanding the Mechanism of B12-Dependent Methylmalonyl-CoA Mutase: Partial Proton Transfer in Action". Journal of the American Chemical Society. 121 (40): 9388–9399. doi:10.1021/ja991649a.
^Kobayashi, Michihiko; Shimizu, Sakayu (1999). "Cobalt proteins". European Journal of Biochemistry. 261 (1): 1–9. doi:10.1046/j.1432-1327.1999.00186.x. PMID 10103026.
primary biological reservoir of cobalt as an ultratrace element. Bacteria in the stomachs of ruminant animals convert cobalt salts into vitamin B12, a compound...
Cobalt therapy is the medical use of gamma rays from the radioisotope cobalt-60 to treat conditions such as cancer. Beginning in the 1950s, cobalt-60 was...
Museum investigating “The Geology, Geometallurgy, and Geomicrobiology of Cobalt Resources Leading to New Product Streams” (joint with Natural History Museum...
Review of Biology. 66 (4): 539. doi:10.1086/417443. JSTOR 2831431. Croquet Consortium Official website Julian Lombardi's Blog Open Cobalt website Croquet...
but an aquarium strain has been selectively bred to achieve a brilliant cobalt blue color. It should not be confused with the burrowing Cambarus monongalensis...
indicator plugs or indicator cards. The active chemical is cobalt chloride (CoCl2). Anhydrous cobalt chloride is blue. When it bonds with two water molecules...
"UV–visible spectroscopic study of the salicyladehyde benzoylhydrazone and its cobalt complexes". Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy...
rate of transportation. Co2+- cobalt ions are present in the human body in amounts from 1 to 2 mg. Cobalt is observed in the heart, liver, kidney, and...
pigments. In the eighth century Chinese artists used cobalt blue to colour fine blue and white porcelain. In the Middle Ages, European artists used it in the...
200-gigabecquerel cobalt-60 capsule, four of whom died. Reports differ as to the source's provenance: it was either found in a dump, found in a field, or was...
that might annihilate mankind. Diagnosed with bladder cancer in 1960, he underwent a cobalt-60 treatment that he had designed. He helped found the Salk...
Historically, the covalent carbon–cobalt bond is one of the first examples of carbon–metal bonds to be discovered inbiology. The hydrogenases and, by necessity...
inorganic chemicals. This experiment in chemistry is usually performed by adding metal salts, such as copper sulfate or cobalt(II) chloride, to an aqueous solution...
Cobalt chelatase (EC 6.6.1.2) is an enzyme that catalyzes the chemical reaction ATP + hydrogenobyrinic acid a,c-diamide + Co2+ + H2O ⇌ {\displaystyle \rightleftharpoons...
produce biogas. In mineral processing, acidophilic archaea display promise for the extraction of metals from ores, including gold, cobalt and copper. Archaea...
element; it has symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly...
in the last decades. Cobalt salts added at low concentration (1 – 2 ppm) were popular in the sixties, but raised the question of cobalt toxicity in case...
the cobalt milkweed beetle or blue milkweed beetle, is a member of the diverse family leaf beetles (Chrysomelidae). It is named after its cobalt-blue...
classified as an element in 1751 by Axel Fredrik Cronstedt, who initially mistook the ore for a copper mineral, in the cobalt mines of Los, Hälsingland...
using megavolt gamma rays emitted by cobalt-60, a radioisotope produced by irradiating ordinary cobalt metal in a reactor, revolutionized the field between...