Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Corphin in context
Nature uses multiple tetrapyrroles - hemes, chlorophyll, and cobalamin. Of the tetrapyrroles with 5 double bonds, F430 is the most reduced. 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.
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.
The biosynthesis of F430 from sirohydrochlorin proceeds via a four steps. The sequence begins with insertion of nickel mediated by a chelatase, similar to that in the biosynthesis of vitamin b12. Subsequent steps include amidation, partial hydrogenation of the pyrrolic backbone, and lactonization.
- Stephen W., Ragdale (2014). "Chapter 6. Biochemistry of Methyl-Coenzyme M Reductase: The Nickel Metalloenzyme that Catalyzes the Final Step in Synthesis and the First Step in Anaerobic Oxidation of the Greenhouse Gas Methane". In Peter M.H. Kroneck and Martha E. Sosa Torres. The Metal-Driven Biogeochemistry of Gaseous Compounds in the Environment. Metal Ions in Life Sciences. 14. Springer. pp. 125–145. doi:10.1007/978-94-017-9269-1_6.
- 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. doi:10.1002/hlca.19910740404.
- 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.
- Zheng K, Ngo PD, Owens VL, Yang XP, Mansoorabadi SO, et al. (October 2016). "The biosynthetic pathway of coenzyme F430 in methanogenic and methanotrophic archaea". Science. 354 (6310): 339–342. doi:10.1126/science.aag2947. PMID 27846569.