Table 2. Primers used for mutagenesis.
| Mutation | Forward primer | Reverse primer |
|---|---|---|
| D61A | CAGAAAGTTATCACTAGAGCTAAGAATAATGTCAATGTGG | CCACATTGACATTATTCTTAGCTCTAGTGATAACTTTCTG |
| K89A | CACTATGAGTACACGGCGAAATTGAACAATTCTATC | GATAGAATTGTTCAATTTCGCCGTGTACTCATAGTG |
| S181A | GAGGGTCAGAAGGTTGCTGTCGATTACATGCTA | TAGCATGTAATCGACAGCAACCTTCTGACCCTC |