Oxidation of carbohydrates by the pea aphid, Macrosiphum pisi (Kltb.).

The nutrition and metabolism of aphids are of interest to biochemists, since these important pests depend upon leaf cell sap for their nutrition and excrete large amounts of carbohydrate and amino acids (1, 2). This suggests that they may have some special nutritional requirements (3), and that their carbohydrate metabolism may possess unusual features. The evidence obtained to date indicates the absence of a hexokinase system, but shows that hexose phosphates are readily utilized. The organism contains the enzymes necessary for oxidation of these compounds by way of the Horecker pentose cycle (4). Thus this cyclic mechanism has been demonstrated in another type of organism differing from higher animals, higher plants, bacteria, or the wheat smut fungus, in which the cycle has been previously established (4-7).