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. 2015 Jan 2;137(3):1372–1382. doi: 10.1021/ja5123842

Table 3. Rate Constants for Turnover of Whole Substrates and the Substrate Pieces Catalyzed by ScOMPDC, ScTIM and hlGPDHa.

enzyme kcat (s–1)b (kcat/Km) (M–1 s–1)b (kcat/Km)E (M–1 s–1)c (kcat/Km)E·HPi (M–1 s–1)c Kd (M)c k′cat (s–1)d
ScOMPDCe 16 1.1 × 107 0.026 1600 ≈ 0.1 ≈ 160f
ScTIM 8900g 2.2 × 108g 0.062h 48h    
hlGPDH 240i 4.6 × 106i 0.050 1100j 0.005 5.5
a

Enzyme-catalyzed reactions of the following whole substrates and substrate pieces: OMPDC; OMP and EO + HPO32–; ScTIM; GAP and GA + HPO32–; hlGPDH; DHAP and GA + HPO32–.

b

Kinetic parameters for turnover of the whole substrate.

c

Kinetic parameter for turnover of the substrate pieces (Schemes 1–3).

d

Rate constant for turnover of the complex between the enzyme and substrate pieces (Scheme 4), estimated as k′cat = [(kcat/Km)E·HPi]Kd.

e

Published kinetic parameters.10

f

Calculated using (kcat/Km)E·HPi = 1600 M–1 s–1 and Kd ≈ 0.1 M.10

g

Kinetic parameters for ScTIM-catalyzed isomerization of GAP.54

h

Table 1.

i

Table 2.

j

Calculated from (kcat/Km)E·X/KX = 16000 M–2 and KX = 0.070 M (Table 2).