Overview of Diverse Methyl/Alkyl-Coenzyme M Reductases and Considerations for Their Potential Heterologous Expression.

Methyl-coenzyme M reductase (MCR) is an archaeal enzyme that catalyzes the final step of methanogenesis and the first step in the anaerobic oxidation of methane, the energy metabolisms of methanogens and anaerobic methanotrophs (ANME), respectively. Variants of MCR, known as alkyl-coenzyme M reductases, are involved in the anaerobic oxidation of short-chain alkanes including ethane, propane, and butane as well as the catabolism of long-chain alkanes from oil reservoirs. MCR is a dimer of heterotrimers (encoded by ) and requires the nickel-containing tetrapyrrole prosthetic group known as coenzyme F.

Lysine 2,3-Aminomutase and a Newly Discovered Glutamate 2,3-Aminomutase Produce β-Amino Acids Involved in Salt Tolerance in Methanogenic Archaea.

Many methanogenic archaea synthesize β-amino acids as osmolytes that allow survival in high salinity environments. Here, we investigated the radical -adenosylmethionine (SAM) aminomutases involved in the biosynthesis of N-acetyl-β-lysine and β-glutamate in C7. Lysine 2,3-aminomutase (KAM), encoded by MmarC7_0106, was overexpressed and purified from followed by biochemical characterization.