Formation of alpha-hydroxyglutaric acid by Aspergillus glaucus

Aspergillus glaucus, cultured on sodium propionate-mineral salts medium, incorporates (14)C-glyoxylate into labeled alpha-hydroxyglutaric acid within 30 sec. Mycelial extracts retain this biosynthetic capacity, which is destroyed by heating. Propionyl-2-(14)C-coenzyme A also in incorporated into labeled alpha-hydroxyglutaric acid by these mycelial extracts, but to a more limited extent. (14)CO(2) evolution studies, employing differentially labeled (14)C-propionate, indicate C-1 is oxidized by the mold before C-2, and C-2 before C-3. These findings suggest the involvement of alpha-hydroxyglutaric acid in the catabolism of propionic acid by A. glaucus.