Table 1. Synthetic oligonucleotides used for site-directed mutagenesis.

Underlined sequences denote the sites indicated; mut, mutated.

Subsitution	Oligonucleotide sequences
Wild-type	Forward: 5′-TGTGGATCCGCGCAATCTGTTCCTTATGGC-3′, BamHI site
	Reverse: 5′-CTGGAGCTCTTGTGCAGCTGCTTGTACGTT-3′, SacI site
Mutant
S33A	Forward: 5′-CGTAAAAGTAGCTGTTATCGACGCAGGAATTGACTCTTCTCATCC-3′, mut site
	Reverse: 5′-GGATGAGAAGAGTCAATTCCTGCGTCGATAACAGCTACTTTTACG-3′, mut site
D60A	Forward: 5′-GAAACAAACCCATACCAGGCAGGCAGTTCTCACGGTA-3′, mut site
	Reverse: 5′-TACCGTGAGAACTGCCTGCCTGGTATGGGTTTGTTTC-3′, mut site
S62A	Forward: 5′-CCATACCAGGACGGCGCTTCTCACGGTACGCAT-3′, mut site
	Reverse: 5′-GGTATGGTCCTGCCGCGAAGAGTGCCATGCGTA-3′, mut site
T220A	Forward: 5′-CGGCGCTTATAACGGAGCATCCATGGCGACTCC-3′, mut site
	Reverse: 5′-GGAGTCGCCATGGATGCTCCGTTATAAGCGCCG-3′, mut site