FIG. 6.

Homology between the putative oxygenase iron binding subunit of Xamo (XAMOA), encoded by aamA, and the iron binding subunits of aromatic ring monooxygenases, MMO, and the R. rhodochrous B276 AMO. Only the sequence around the iron binding sites is shown. Dark highlighting indicates residues which are identical or functionally conserved in at least four sequences. The glutamate and histidine ligands that coordinate the binuclear iron center (24) in MMO (and are completely conserved in the other homologs) are shown as subscripts in capital letters, and the residues referred to in the text are indicated by triangles. TMOA, BMOA, AMOB, and MEMA, iron binding subunits from the P. mendocina KR1 toluene 4-monooxygenase (39), the Pseudomonas aeruginosa JI 104 benzene monooxygenase (16), the R. rhodochrous B276 AMO (25), and the M. trichosporium OB3b MMO (5), respectively.