The requirement for cobalt in vitamin B12: A paradigm for protein metalation

Deenah Osman, Anastasia Cooke, Tessa R. Young, Evelyne Deery, Nigel J. Robinson, Martin J. Warren

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64 Citations (Scopus)
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Vitamin B12, cobalamin, is a cobalt-containing ring-contracted modified tetrapyrrole that represents one of the most complex small molecules made by nature. In prokaryotes it is utilised as a cofactor, coenzyme, light sensor and gene regulator yet has a restricted role in assisting only two enzymes within specific eukaryotes including mammals. This deployment disparity is reflected in another unique attribute of vitamin B12 in that its biosynthesis is limited to only certain prokaryotes, with synthesisers pivotal in establishing mutualistic microbial communities. The core component of cobalamin is the corrin macrocycle that acts as the main ligand for the cobalt. Within this review we investigate why cobalt is paired specifically with the corrin ring, how cobalt is inserted during the biosynthetic process, how cobalt is made available within the cell and explore the cellular control of cobalt and cobalamin levels. The partitioning of cobalt for cobalamin biosynthesis exemplifies how cells assist metalation.
Original languageEnglish
Article number118896
JournalBiochimica et Biophysica Acta (BBA) - Molecular Cell Research
Issue number1
Early online date21 Oct 2020
Publication statusPublished - Jan 2021


  • Chelation
  • Cobalamin
  • Cobamide
  • Homeostasis
  • Metals
  • sensors

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