Identification and characterization of two isozymic forms of arylamine n-acetyltransferase in syrian hamster skin

Stephen J. Gaudet, Andrzej Slominski, Mohammad Etminan, Daniel Pruski, Ralf Paus, M. A.A. Namboodiri

Research output: Contribution to journalArticle

44 Scopus citations


Arylamine N-acetyltransferase (EC activity was examined using skin from Syrian hamster. Two isozymes of arylamine N-acetyltransferase, designated NAT-1 and NAT-2, were detected on anion-exchange high-performance liquid chromatography analysis. Both enzyme activities had indistinguishable molecular masses (30 kDa), but differed significantly in their specificity toward the aromatic amines including serotonin, dopamine, methoxytryptamine, tryptamine, para-phenetidine, para-aminobenzoic acid, and sulphamethazine. Specifically, NAT-2 but not NAT-1 catalyzed acetylation of dopamine to N-acetyldopamine and acetylation of serotonin to form N-acetylserotonin, a direct precursor of melatonin. The two isozymes were also distinguishable based upon their sensitivity toward methotrexate inhibition (50% inhibiting dose for NAT-1 = 380 μM; NAT-2 > 2 mM). The presence of these two activities in the skin raises new questions about the physiologic role of this enzyme in general and in the skin-specific functions in particular.

Original languageEnglish (US)
Pages (from-to)660-665
Number of pages6
JournalJournal of Investigative Dermatology
Issue number5
StatePublished - Nov 1993
Externally publishedYes



  • N-acetyldopamine
  • N-acetylserotonin
  • detoxification
  • melatonin

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Dermatology
  • Cell Biology

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