Detection of precursors of quinolinic acid in Escherichia coli.

A technique is described which allows the detection of precursors of quinolinic acid produced by Escherichia coli, independent of a bioassay. This is based on a double autoradiogram utilizing radioactive aspartic acid and fructose-1,6-diphosphate (as a source of dihydroxyacetone phosphate). Six radioactive spots are derived from aspartic acid and four are derived from fructose-1,6-diphosphate. The latter four spots correspond to four of the former spots in migration in each of two solvent systems. The significance of these data relative to genetic and enzymatic data is discussed.