Sequence comparison between Geobacillus CuNIR and well known CuNIRs. Abbreviations and accession numbers are as follows: GkNIR, GK0767 from G. kaustophilus strain HTA426 (gi:56419302); NgNIR, CuNIR from N. gonorrhoeae strain FA1090 (gi:59718528); AxNIR, CuNIR from A. xylosoxidans strain GIFU1051 (gi:3721763). ClustalW was used to perform sequence alignment (Thompson et al., 1994 ▶) and the figure was generated using the program ESPript (Gouet et al., 1999 ▶). Diamonds, type 1 Cu ligands; squares, type 2 Cu ligands. The three characteristic loop regions in GkNIR are shown in coloured boxes: green, linker loop; blue, tower loop; orange, extra loop.