Crystal structure of a membrane-bound metalloenzyme that catalyses the biological oxidation of methane

@article{Lieberman2005CrystalSO,
  title={Crystal structure of a membrane-bound metalloenzyme that catalyses the biological oxidation of methane},
  author={Raquel L. Lieberman and Amy C. Rosenzweig},
  journal={Nature},
  year={2005},
  volume={434},
  pages={177-182}
}
Particulate methane monooxygenase (pMMO) is an integral membrane metalloenzyme that catalyses the conversion of methane to methanol. Knowledge of how pMMO performs this extremely challenging chemistry may have an impact on the use of methane as an alternative energy source by facilitating the development of new synthetic catalysts. We have determined the structure of pMMO from the methanotroph Methylococcus capsulatus (Bath) to a resolution of 2.8 Å. The enzyme is a trimer with an α3β3γ3… 

The quest for the particulate methane monooxygenase active site.

TLDR
The state of knowledge before and after the structure determination of pMMO is reviewed, emphasizing elucidation of the pM MO active site.

Structural conservation of the B subunit in the ammonia monooxygenase/particulate methane monooxygenase superfamily

TLDR
The crystal structure of the corresponding domain of an archaeal amoB subunit from Nitrosocaldus yellowstonii has been determined and reveals a remarkable conservation of overall fold and copper binding site location as well as several notable differences that may have implications for function and stability.

Architecture and active site of particulate methane monooxygenase

TLDR
Biochemical and spectroscopic data on pMMO and recombinant soluble fragments, denoted spmoB proteins, indicate that the active site involves copper and is located at the site of the dicopper center in the pmoB subunit.

Controlled oxidation of hydrocarbons by the membrane-bound methane monooxygenase: the case for a tricopper cluster.

TLDR
Evidence is described that pMMO is a multicopper protein that mediates dioxygen chemistry and O-atom transfer during alkane hydroxylation and designed and synthesized model tricopper clusters to provide further chemical evidence that a tricoppers cluster mediates the enzyme's oxo-transfer chemistry.

The model structure of the copper-dependent ammonia monooxygenase

TLDR
A successful attempt to build a structural model of ammonia monooxygenase, and its accessory proteins AmoD and AmoE, from Nitrosomonas europaea, taking advantage of the high sequence similarity with particulate methane mono oxygengenase and the homologous PmoD protein, for which crystal structures are instead available.

Particulate Methane Monooxygenase

TLDR
Although the identity of the pMMO active site remains unknown, some information regarding the mechanism has been obtained from substrate studies and computational work.

From micelles to bicelles: Effect of the membrane on particulate methane monooxygenase activity

TLDR
These findings suggest that loss of pMMO activity upon isolation is due to removal from the membranes rather than caused by loss of the catalytic copper ions, and underscore the importance of studying membrane proteins in a membrane-like environment.

A tale of two methane monooxygenases

TLDR
The current state of knowledge for both enzymes is reviewed, and pMMO O2 activation intermediates suggested by computational and synthetic studies in the context of existing biochemical data are considered.
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