Acetylation of aromatic cysteine conjugates by recombinant human N-acetyltransferase 8. (4th March 2017)

• Record Type: Journal Article
• Authors: Deol, Reema; Josephy, P. David
• Is Part Of: Xenobiotica. Volume 47:Number 3(2017)
• Page Start: 202
• Page End: 207
• Publication Date: 2017-03-04
• Subjects: Benzylcysteine -- 4-nitrobenzylcysteine -- mercapturic acid pathway -- NAT8 -- N-acetyltransferase -- 1-menaphthylcysteine; Metabolism -- Periodicals; Drugs -- Physiological effect -- Periodicals; Food additives -- Periodicals; Chemicals -- Physiological effect -- Periodicals; Biochemistry -- Periodicals; Pharmaceutical Preparations -- metabolism -- Periodicals; Metabolism -- Periodicals; 574.133
• DOI: 10.1080/00498254.2016.1178410
• Languages: English
• ISSNs: 0049-8254

Abstract

Abstract: 1. The mercapturic acid (MA) pathway is a metabolic route for the processing of glutathione conjugates to MA ( N -acetylcysteine conjugates). An N -acetyltransferase enzyme, NAT8, catalyzes the transfer of an acetyl group from acetyl-CoA to the cysteine amino group, producing a MA, which is excreted in the urine. We expressed human NAT8 in HEK293T cells and developed an HPLC-MS method for the quantitation of the S -aryl-substituted cysteine conjugates and their MA. 2. We measured the activity of the enzyme for acetylation of benzyl-, 4-nitrobenzyl-, and 1-menaphthylcysteine substrates. 3. NAT8 catalyzed the acetylation of all three cysteine conjugates with similar Michaelis–Menten kinetics.