The active site structure of methane monooxygenase is closely related to the binuclear iron center of ribonucleotide reductase

FEBS Letters

Eklund, Hans¹  Nordlund, Pär¹  Dalton, Howard² 

[1] Department of Molecular Biology, Swedish University of Agriculture Sciences, Biomedical Center, Box 590, S-751 24 Uppsala, Sweden;Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK

关键词: Active site model;    Binuclear iron protein;    Gene duplication;    Methane monooxygenase;    Ribonucleotide reductase;   

DOI  :  10.1016/0014-5793(92)80690-I

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Methane monooxygenase (MMO) catalyses the biological transformation of methane to methanol at a binuclear iron site. Guided by the three-dimensional structure of the R2 protein of E. coli ribonucleotide reductase (RNR), we have aligned the sequences of two different MMOs with the sequences of the iron coordinating four helix bundle in R2. The model suggests that the central four helix bundle of R2 is present also in MMO. The iron coordination is similar in MMO and R2 with two histidine ligands and four carboxyl ligands in both cases. The residues lining the proposed oxygen binding site in MMO are significantly smaller in MMO than in R2 allowing binding of both molecular oxygen and methane at this site. This binding site is lined by residues Cys¹⁵¹, Thr²¹³, Ile²¹⁷ and Ile(Val)²³⁹.

【 授权许可】

Unknown