title: Configuration assignments of the amino acid residues and the presence of N-methyldehydroalanine in toxins from the blue-green alga, Microcystis aeruginosa.
abstract: The configuration assignment of the alpha-carbon atom of amino acid residues in four toxin variants from Microcystis aeruginosa have been made by stereospecific enzymic transformations. The relative conformation assignment of the beta-carbon atom of beta-CH3-aspartic acid could be made by comparison of the electrophoretic mobility with literature values reported for the authentic compound. The presence of an N-methyldehydroalanine residue, which, due to elimination of methylamine under hydrolytic conditions, previously escaped detection by conventional means, has been confirmed by identification of N-methylalanine in the hydrolysate after reduction of toxin with sodium borohydride.
mesh_terms: D000409:Alanine / Q000031:analogs & derivatives* / Q000032:analysis; D000596:Amino Acids / Q000032:analysis*; D004586:Electrophoresis; D046931:Microcystis / Q000032:analysis*; D008968:Molecular Conformation; D014118:Toxins, Biological / Q000032:analysis*
chemical_list: D000596:Amino Acids; D014118:Toxins, Biological; C037064:N-methyldehydroalanine; D000409:Alanine