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. 2015 Sep 22;81(20):7187–7200. doi: 10.1128/AEM.02028-15

TABLE 6.

Enzyme kinetic parameters used in modela

Enzyme Rate law kcatfwd (s−1) kcatrev (s−1) Kmb
KI (μM) Keqc Reference(s)
Substrate Concn(μM)
Thl Bi bi ping pong 53.9 987d C2-CoA 271 2.8 × 10−5 This work; 74
AcAc-CoA 33 133
CoA 15 73
Hbd Irreversible bi 35 AcAc-CoA 18.7 (180) This work
Crt Uni uni 267 267e 3HB-CoA 107 0.22 This work
Crot-CoA 30 75
Ter Irreversible bi 47.7 Crot-CoA 49.9 (1.2 × 109) This work
NADH 38.9
X514-Bad Ordered bi ter 4.54 (C2-CoA) 116 (C2)f C2-CoA 83.6 0.14 M This work
C4-CoA 27.2
22.7 (C4-CoA) 573 (C4)f C2 3,700 6.0 M 47
C4 3,700
X514-Bdh Irreversible bi 7.7 (C2) C2 3,330 (790) This work
10.4 (C4) C4 2,030 (2,200)
Ctherm-AdhE Ordered bi ter 3.3 (C2-CoA) 82.2 (C2)f C2-CoA 11.5 0.14 M This work
2.3 (C4-CoA) 57.8 (C4)f C4-CoA 15.0 6.0 M 47
Irreversible bi 3.6 (C2) C2 7,760 (790) This work
15.4 (C4) C4 6,920 (2,200)
X514-AdhE Ordered bi ter 3.6 (C2-CoA) 90.3 (C2)f C2-CoA 9.4 0.14 M This work
2.3 (C4-CoA) 56.8 (C4)f C4-CoA 5.71 6.0 M 47
Irreversible bi 23.0 (C2) C2 22,000 (790) This work
22.9 (C4) C4 3,230 (2,200)
a

Abbreviations: C2-CoA, acetyl-CoA; AcAc-CoA, acetoacetyl-CoA; 3HB-CoA, 3-hydroxybutyryl-CoA; Crot-CoA, crotonyl-CoA; C2-CoA, butyryl-CoA; C2, acetaldehyde; C4, butyraldehyde; CoA, coenzyme A.

b

Km values for NADH, NAD, and CoA are assumed to be 50 μM unless otherwise specified.

c

Equilibrium constants calculated using eQuilibrator (76) at pH 7.9 and ionic strength of 0.1 M. The italic values shown in parentheses do not affect the reaction rate, because the reaction is modeled as irreversible.

d

Based on reference 74, assuming a constant ratio of kcatfwd to kcatrev.

e

Assumed to be equal to kcatfwd.

f

Based on reference 47, assuming a constant ratio of kcatfwd to kcatrev.