Studies in the biochemistry of micro-organisms

THE study of the metabolic processes of different cinnamon to brown strains in the Aspergillus terreus Thom series has formed the subject of a number of com- munications from these laboratories. Raistrick & Smith [1935] reported that two strains out of five grown on Czapek-Dox solution gave a hitherto undescribed mould metabolic product-terrein, C8H1003-which was shown by Clutterbuck et al. [1937, 2] to be 4-propenyl-2-hydroxy-3: 5-oxidocyclopentane-1-one. One of these two strains gave, in addition to terrein, considerable quantities of citrinin, C,,H,40,, a crystalline yellow colouring matter previously reported as a metabolic product of Penicillium citrinum Thom by Hetherington & Raistrick [1931]. Of the other three strains of A. terreus one gave succinic acid, another oxalic acid, while the third strain gave a mixture of these two acids. In a later communication Raistrick & Smith [1936] showed that one of the five strains previously examined by them, which produced terrein also, metabolized almost the whoJe of the chloride supplied as KCI in the Czapek-Dox solution and gave rise to two new chlorine-containing metabolic products, geodin C17Hl207C12 and erdin C18H1007C12, the molecular constitutions of which have been investigated [Clutterbuck et al. 1937, 1; Calam et al. 1939].