69168-08-7Relevant academic research and scientific papers
Ergothioneine biosynthetic methyltransferase EgtD reveals the structural basis of aromatic amino acid betaine biosynthesis
Vit, Allegra,Misson, La?titia,Blankenfeldt, Wulf,Seebeck, Florian P.
, p. 119 - 125 (2015/03/03)
Ergothioneine is an N-α-trimethyl-2-thiohistidine derivative that occurs in human, plant, fungal, and bacterial cells. Biosynthesis of this redox-active betaine starts with trimethylation of the α-amino group of histidine. The three consecutive methyl transfers are catalyzed by the S-adenosylmethionine-dependent methyltransferase EgtD. Three crystal structures of this enzyme in the absence and in the presence of N-α-dimethylhistidineand S-adenosylhomocysteine implicate a preorganized array of hydrophilic interactions as the determinants for substrate specificity and apparent processivity. We identified two active site mutations that change the substrate specificity of EgtD 107-fold and transform the histidine-methyltransferase into a proficient tryptophan-methyltransferase. Finally, a genomic search for EgtD homologues in fungal genomes revealed tyrosine and tryptophan trimethylation activity as a frequent trait in ascomycetous and basidomycetous fungi.
Characterization of amino acid-derived betaines by electrospray ionization tandem mass spectrometry
Naresh Chary,Dinesh Kumar, Ch.,Vairamani,Prabhakar
experimental part, p. 79 - 88 (2012/05/04)
Betaines belong to the naturally occurring osmoprotectants or compatible solutes present in a variety of plants, animals and microorganisms. In recent years, metabolomic techniques have been emerging as a fundamental tool for biologists because the constellation of these molecules and their relative proportions provide with information about the actual biochemical condition of a biological system. Therefore, identification and characterization of biologically important betaines are crucial, especially for metabolomic studies. Most of the natural betaines are derived from amino acids and related homologues. Although, theoretically, all the amino acids can be converted to corresponding betaines by simple methylation of the amine group, only a few of the amino acid-derived betaines were fully characterized in the literature. Here, we report a combined electrospray ionization tandem and high-resolution mass spectrometry study of all the betaines derived from amino acids, including the isomeric betaines. The decomposition pathway of protonated, sodiated and potassiated molecule ions that enable unambiguous characterization of the betaines including the isomeric betaines and overlapping ionic species of different betaines is distinctive. Copyright
Thermodynamic view of hydrophobic association of side chains of aromatic amino acids
Iyengar, R. R.,Bhattacharya, P. K.
, p. 445 - 451 (2007/10/02)
The hydrophobic association constants, K, for the side chains of phenylalanine, tyrosin and tryptophan betains have been evaluated employing the difference in the mode of self-association of the optically pure L-betains and their DL-mixtures and using the
