Investigation And Application Of Acetransferases Targeting At Small Amino-Molecules

GCN5-related N-acetyltransferases are conserved in all domain of life,and catalyze the transfer of the acetyl from the acetyl-coenzyme A(Ac-CoA)donor to a primary amine of small molecules and proteins.In this article,we focus on the function of two kinds of different acetyltransferase,respectively is aminoglycoside acetyltransferase Eis and biogenic amine acetyltransferase aaNAT.Recently,a chromosomal encoded protein Eis(enhanced intracellular survival protein)was found responsible for aminoglycoside antibiotics resistance in Mycobacterium tuberculosis.MtbEis belongs to a novel family of hexameric acetyltransferases,whose tripartite fold is composed of two GCN5 N-acetyltransferase regions and a sterol carrier protein fold.In this study,we investigate the SCP2 containing GCN5-related acetyltransferase,SenEis from Saccharopolyspora erythraea.Oleic acid was identified as ligands by monitoring the conformational changes that occur upon lipid acids binding to the SCP2 domain in SenEis protein using fluorescence resonance energy transfer(FRET)biosensor.We observed that the oleic acid stimulated the activity of aminoglycoside acetyltransferase SenEis on acetylation of aminoglycoside(AG)antibiotics and acetyl-CoA synthetase.Furthermore,the vital residues involved in binding of oleic acid in the SCP2 domain of SenEis were investigated.Here,we describes a unique functional interplay between a SCP2 domain and aminoglycoside acetyltransferase.Biogenic amines are basic nitrogenous compounds with at least one primary amine group,mainly derived from the decarboxylation of their precursor amino acids.The presence of biogenic amines in food usually pose a public health concern,due to their physiological and toxicological effects.The main obstacle for direct detection of biogenic amines lies in their structures,which contain no chromophoric or fluorophoric moieties.We developed a novel colorimetric method for rapid detection of biogenic amines based on arylalkylamin N-acetyltransferase(aaNAT).aaNAT transfers an acetyl group from AcCoA to biogenic amines in the presence of DTNB,resulting in the formation of TNB2",which absorbs strongly at 412 nm.This method offers distinct advantages including simple handling,speed,low cost,high sensitivity,and good selectivity.