Table 1. List of the site-directed mutants and the site-specific oligonucleotides used in this study.

Mutanta	Sequenceb
D363A	5′-CGCCGTTTTGACGAGTGCTATCCACGTTGGAAGCAAGG-3′
H365A	5′-CGCCGTTTTGACGAGTGATATCGCCGTTGGAAGCAAGG-3′
D407A	5′-GGTATTTAATTATAGCAGGGGCTGTTGTCGATGGCATCGGAATTTATCCTGGCC-3′
D410A	5′-GGTATTTAATTATAGCAGGGGATGTTGTCGCTGGCATCGGAATTTATCCTGGCC-3′
D421A	5′-CCTGGCCAGTATTCTGCCCTAATAATTCCCGATATC-3′
N453A	5′-GATCTTCATAGGCCCCGGTGCTCATGATGCTGCAAGGC-3′
N454A	5′-CTTCATAGGCCCCGGTAATGCTGATGCTGCAAGGCCC-3′
N479A	5′-GCCCCTGTATAAGTTGAAGGCTACTGTGATAATCAGCAACCC-3′
H492A	5′-CCAGCGGTCATAAGGCTTGCTGGTAGGGATTTTTTGATAG-3′
H500A	5′-GGGATTTTTTGATAGCCGCTGGAAGGGGAATAGAGGATG-3′
E553A	5′-GAGGATCTATTGGTAATAGCTGAAGTTCCGGATCTAGTTC-3′
D557A	5′-GTAATAGAGGAAGTTCCGGCTCTAGTTCAGATGGGACATG-3′
H563A	5′-GATCTAGTTCAGATGGGAGCTGTGCATGTTTACGATACTGCGG-3′
H565A	5′-GATCTAGTTCAGATGGGACATGTGGCTGTTTACGATACTGCGG-3′

^aThe mutants in bold indicate residues putatively involved in metal binding; the mutants in italics indicate residues probably involved in catalytic assistance and the rest of the mutations are residues conserved among DP1 species.

^bOnly forward sequences are shown. Codes underlined indicate the sites of mutations.