The alkene monooxygenase from Xanthobacter Py2 is a binuclear non-haem iron protein closely related to toluene 4-monooxygenase.
The genes encoding the six polypeptide components of the alkene monooxygenase from Xanthobacter Py2 have been sequenced. The predicted amino acid sequence of the first ORF shows homology with the iron binding subunits of binuclear non-haem iron containing monooxygenases including benzene monooxygenase, toluene 4-monooxygenase (> 60% sequence similarity) and methane monooxygenase (> 40% sequence similarity) and that the necessary sequence motifs associated with iron co-ordination are also present. Secondary structure prediction based on the amino acid sequence showed that the predominantly alpha-helical structure that surrounds the binuclear iron binding site was conserved allowing the sequence to be modelled on the co-ordinates of the methane monooxygenase alpha-subunit. Significant differences in the residues forming the hydrophobic cavity which forms the substrate binding site are discussed with reference to the differences in reaction specificity and stereospecificity of binuclear non-haem iron monooxygenases.
Department of Biochemistry, Imperial College of Science, Technology and Medicine, London, UK.
N Y
NY
Zhou
A
A
Jenkins
C K
CK
Chan Kwo Chion
D J
DJ
Leak
D000595:Amino Acid Sequence; D001665:Binding Sites; D017124:Conserved Sequence / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics; D006088:Gram-Negative Aerobic Bacteria / Q000201:enzymology* / Q000235:genetics; D007501:Iron / Q000737:chemistry; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010105:Oxygenases / Q000737:chemistry* / Q000235:genetics; D017433:Protein Structure, Secondary; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
D007501:Iron; D010105:Oxygenases; C072883:alkene monooxygenase; C068610:toluene-4-monooxygenase