Bacillus subtilis contains urease structural genes but lacks the accessory genes typically required for GTP-dependent incorporation of nickel. Nevertheless, B. subtilis was shown to possess a functional urease, and the recombinant enzyme conferred low levels of nickel-dependent activity to Escherichia coli. Additional investigations of the system lead to the suggestion that B. subtilis may use unidentified accessory proteins for in vivo urease activation.