Lanthanide-dependent methanol dehydrogenase
From Wikipedia, the free encyclopedia
| Lanthanide-dependent methanol dehydrogenase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 The enzyme as folded by AlphaFold | |||||||||
| Identifiers | |||||||||
| EC no. | 1.1.2.10 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| |||||||||
Lanthanide-dependent methanol dehydrogenase[a] is an oxidoreductase enzyme involved in methane metabolic pathways in microbial metabolism. This enzyme was first isolated from the methylacidiphilum fumariolicum and others in the methylacidiphilum species. The enzyme requires La3+, Ce3+, Pr3+ or Nd3+. Higher lanthanides show decreasing activity with Sm3+, Eu3+ and Gd3+. The lanthanide atom in the enzyme is coordinated by pyrroloquinoline quinone.[1] The enzyme catalyzes the following reaction:
- 2 Fe(III)-cytochrome cL + methanol -> 2 Fe(II)-cytochrome cL + formaldehyde + 2 H+
Methylotrophic bacteria are those that consume one-carbon and methylated compounds as the primary carbon source. These bacteria have been known for a century and are largely important in methane and methanol biogeochemical cycles. For the majority of the history of studies on these enzymes, pyrroloquinoline quinone (PQQ)-dependent methanol dehydrogenases were said to be the primary enzymes for the oxidation of methanol.[2] The machinery of the PQQ-dependent enzyme is largely Conserved among the α, β, and γ-protebacteria.
The discovery of lanthanide-dependent methanol dehydrogenases changed this belief, originally a seen as a homolog of MoxF. Several of these enzymes showed methanol dehydrogenase activity in the presence of lanthanide ions such as Ln3+. In the study of metaloenzymes, it was originally believed that Ln3+ was biologically unimportant, but the discovery of Ln3+-dependent AHDs revealed more about the biological activity of lanthanides.[3][4]
Structure
In the homodimeric Ce3+-dependent methanol dehydrogenase sampled from methylacidiphilum fuimariolicum SolIV, the active site consists of glutamate, asparagine and aspartic acid residues that form a coordination complex for the Cerium ion. In protein crystallization studies, a molecule of polyethylene glycol occupies a substrate binding coordination position of Ce3+. The bacterial enzymes are known to interact with two cytochromes, cL and cH. Once methanol is oxidized, PQQ is reduced. The re-oxidation of PQQ is facilitated through the stepwise electron transfer to the cytochromes.[5]
