TABLE 1

Kinetic properties of FN3K and FN3K-RP

FN3K (ketosamine 3-kinase 1)
FN3K-RP (ketosamine 3-kinase 2)
KM (μmol/l)Vmax (mU/mg)I50 lys-allose (μmol/l)I50 lys-riboseKM (μmol/l)Vmax (mU/mg)I50 (μmol/l)I50 lys-ribose
Deoxymorpholino- fructose104667 ± 22 (n = 3)≈20 mmol/lNo substrate
No inhibition at 25 mmol/lNo inhibition at 25 mmol/l
Deoxymorpholino-psicose1602969026% inhibition at 5 mmol/l (n = 2)16041580 ± 70 (n = 4)≤10% inhibition at 5 mmol/l
Psicoselysine14054720 ± 110 (n = 4)≤10% inhibition at 5 mmol/l270 ± 10 (n = 3)40 ± 3 (n = 3)480≤10% inhibition at 5 mmol/l
Deoxymorpholino-ribulose2.6 ± 0.1 (n = 4)53.628 ± 7% inhibition at 100 μmol/l (n = 6)3.5 ± 0.1 (n = 3)16 (n = 3)6.4 ± 1.0 (n = 4)35 ± 3% inhibition at 100μmol/l
  • Data are the means of two values or means ± SE. For both enzymes, the first two columns indicate the KM and Vmax values for the indicated compounds. The third and fourth columns show the concentrations of compounds needed to cause 50% inhibition of the enzymatic activity (I50) determined on lysozyme glycated with allose or with ribose or the inhibition reached at the indicated concentration. The preparation of enzymes used were purified recombinant human FN3K expressed in E. coli (16) and FN3K-RP purified from HEK-293 cells. For the calculation of the Vmax, the concentration of FN3K or FN3K-RP was estimated from SDS-PAGE gels that had been stained with Coomassie Blue by comparison with standards.