 Methanogenesis, the biosynthesis of methane, entails as its final step, the scission of a nickel-methyl bond in cofactor F430.The iron-molybdenum cofactor (FeMoco) of nitrogenases contains an Fe6C unit and is an example of an interstitial carbide found in biology.A pincer complex containing a nickel-aryl bond has been reported to form the active site of lactate racemase.