This PAI-1 mutant has an amino acid replacement of Serine to Cysteine at the vitronectin binding site. An NBD label is incorporated for which allows for the detection of vitronectin binding.

References
1. Minor KH et al. (2002) J Biol Chem 277: 10337-10345.
2. Backovic et al. (2002) Prot Sci 11: 182-1191.