The resulting 1,3-dipole reductively acetylates lipoamide-E2. Hat1 acetylates H4K5 and H4K12, and Hpa2 acetylates H3K14 "in vitro". During S phase, Eco1 acetylates lysine residues in the Smc3 subunit of cohesin. During S phase, Eco1 (Esco1/Esco2 in humans) acetylates Smc3. This protein acetylates both histone and non-histone proteins. KAT5 acetylates histones on genes of these transcription factors, which promote their activity. Human NAT1 preferentially acetylates 4-aminobenzoic acid (PABA), 4 amino salicylic acid, sulfamethoxazole, and sulfanilamide. In reaction one acetyl-CoA initially binds to the enzyme and acetylates Cys.