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Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
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 bacteria that are thought to be involved in reverse methanogenesis. Organisms that promote this remarkable reaction contain 7% by weight nickel protein.3
- 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.
- 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.
- 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.