Table 1: Summary of pKa values for hDDC.

Parameter pH-independent valuepK1pK2

5.1 ± 0.4 s−16.3 ± 0.17.9 ± 0.1
/Km174 ± 3 mM−1s−16.1 ± 0.1
Absorbance at 420 nm pH titration 7.2 ± 0.1
Absorbance at 335 nm pH titration7.3 ± 0.1
Emission fluorescence pH titration (exc. 335 nm)
 emis.384 nm7.3 ± 0.1
 emis.504 nm7.2 ± 0.1
Emission fluorescence pH titration (exc. 420 nm)
7.2 ± 0.1
Amplitude ext. ald. 390 nm6.4 ± 0.3
KD(PLP)8.3 ± 0.2