Further Pigments, Containing Nitrogen

In Agaricus campester ( = A. campestris) an intermediate in the oxidative sequence (544) (543) (542) occurs in the form of the amino 

Labelling experiments have confirmed that the aromatic moiety of y-L-glutaminyl-4-hydroxybenzene (544) is formed via shikimic acid in A. bisporus (635, 664). It is probably a metabolite of p-aminobenzoic acid as is the closely related compound agaritine (553) (668). p-Amino-benzoic acid may be oxidatively decarboxylated to yield p-aminophenol and thence (544). 

The role of these aromatic metabolites in the fruit bodies is not known with certainty but they have been implicated in the control of sporulation (109, 538, 706) and as precursors in the formation of spore wall melanin (i5S, 635). 

Several Agaricus species suffer reddening of the flesh on bruising. This phenomenon may be ascribed to the presence of the red quinones 

When fruit bodies of A. xanthoderma were extracted with cold ethyl acetate and the yellow extracts were concentrated and chromatographed at low temperature, the red crystalline pigment agaricone (549) 

---