Table 2.

Comparison of kinetic constants for HAT catalyzed acetyl transfer

HAT	kcat, s−1	Km AcCoA, µM	Km peptide, µM	Reference
p300	4.1 ± 0.1 × 100	40 ± 0.6	1.6 ± 0.1 × 102a	[26•]
Gcn5	1.7 ± 0.1 × 100	2.5 ± 1.4	4.9 ± 0.8 × 102 b	[18]
Rtt109	1.7 ± 0.1 × 10−3	0.3 ± 0.1	8.3 ± 2.9 × 101 c	[29•]
Rtt109•Vps75	1.3 ± 0.4 × 10−1	1.0 ± 0.2	7.5 ± 1.5 × 101 c	[29•]
Esa1	1.9 ± 1.0 × 10−3	1.0 ± 0.4	1.4 ± 1.0 × 103 d	[40]; C.E.B. and J.M.D., unpublished data
Piccolo NuA4	1.6 ± 0.1 × 100	2.5 ± 0.3	2.2 ± 0.3 × 102 d	[23•]

^aCalculated using a peptide of H4 residues 4 to 15

^bCalculated using a peptide of H3 residues 1 to 20 plus a C-terminal cysteine

^cCalculated using a peptide of H3 residues 1 to 20

^dCalculated using a peptide of H4 residues 1 to 20