Structure of MMOH active site

The crystallographic structures of MMOH from both microorganisms, Methylococcus capsulatus (Bath) and Methylosynus trichosporium OB3b have been 

No obvious evidence concerning substrate entry to the diiron cluster have been revealed indicating that the entry channel may be opened due to the proteins spontaneous flexibility or may be created by binding MMOB or MMOR (Wallar and Lipscomb, 1996). Recent data on crystal structure of MMOH from M. capsulatus demonstrate the geometric variability of the enzyme active site (Whittington et al., 2001). It is shown, that ferrous atoms, adjacent a-helix, and the Asn214 group have a certain pliability, which enables small molecules to penetrate into the active site. 

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