Cofactor F430

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Cofactor F430
Coenzyme F430.svg
Identifiers
CAS number 73145-13-8 YesY
PubChem 5460020
Properties
Molecular formula C
42
H
51
N
6
NiO
13
Molar mass 906.58014
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

F430 is the prosthetic group of the enzyme methyl coenzyme M reductase. It is found only in methanogenic Archaea.[1] This enzyme catalyzes the release of methane in the final step of methanogenesis:

CH
3
–S–CoM
+ HS–CoBCH
4
+ CoB–S–S–CoM

Corphin in context[edit]

Nature uses multiple tetrapyrroles - hemes, chlorophyll, and cobalamin. F430 is the most reduced tetrapyrrole in nature with only five double bonds. This particular tetrapyrrole derivative is called a corphin. Because of its relative lack of conjugated unsaturation, it is yellow, not the intense purple-red associated with more unsaturated tetrapyrroles. It is also the only tetrapyrrole derivative found in nature to contain nickel. Ni(II) is too small for the N4 binding site of the corphin, which causes the macrocycle to adopt a ruffled structure. Its structure was deduced by X-ray crystallography and NMR spectroscopy.[2]

F430 occurs in particularly high concentrations in archaea that are thought to be involved in reverse methanogenesis. Organisms that promote this remarkable reaction contain 7% by weight nickel protein.[3]

References[edit]

  1. ^ Thauer RK (1998). "Biochemistry of Methanogenesis: a Tribute to Marjory Stephenson". Microbiology 144 (9): 2377–2406. doi:10.1099/00221287-144-9-2377. PMID 9782487. 
  2. ^ Färber G, Keller W, Kratky C, Jaun B, Pfaltz A, Spinner C, Kobelt A, Eschenmoser A (1991). "Coenzyme F430 from Methanogenic Bacteria : Complete Assignment of Configuration Based on an X-ray Analysis of 12,13-diepi-F430 Pentamethyl Ester and on NMR Spectroscopy". Helvetica Chimica Acta 74: 697–716. doi:10.1002/hlca.19910740404. 
  3. ^ Krüger M, Meyerdierks A, Glöckner FO, et al. (December 2003). "A conspicuous nickel protein in microbial mats that oxidize methane anaerobically". Nature 426 (6968): 878–81. doi:10.1038/nature02207. PMID 14685246.