Table 2 Steady-state Kinetic Constants for Acyl-CoA Substrates at a Fixed Initial Concentration of Agmatinea ,b.

From: Structural and Mechanistic Analysis of Drosophila melanogaster Agmatine N-Acetyltransferase, an Enzyme that Catalyzes the Formation of N-Acetylagmatine

Substrate (Range)c,d

Km,app (µM)

kcat,app (s−1)

(kcat/Km)app (M−1s−1)

Acetyl-CoA (10–500 mM)

(1.0 ± 0.06) × 102

23 ± 1

(2.2 ± 0.2) × 105

Butyryl-CoA (1.0–750 mM)

(4.0 ± 0.6) × 101

3.3 ± 0.1

(8.0 ± 1) × 104

Hexanoyl-CoA (50–1000 mM)

(1.1 ± 0.03) × 102

1.1 ± 0.04

(9.7 ± 0.6) × 103

Octanoyl-CoA (25–1000 mM)

(1.4 ± 0.1) × 102

0.61 ± 0.02

(4.4 ± 0.4) × 103

Decanoyl-CoA (50–2500 mM)

(7.0 ± 1) × 101

0.16 ± 0.01

(2.2 ± 0.3) × 103

  1. aKinetic constants are reported as ± standard error (n = 3). bReaction conditions −300 mM Tris-HCl pH 8.5, 150 µM DTNB, 5 mM agmatine, and varying concentration of acyl-CoA. cThe range of acyl-CoA concentrations used in determining the Km,app values at the constant, fixed initial concentration of agamatine (5 mM). dOleoyl-CoA was not accepted as substrate by AgmNAT.
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