Site and Mode of Trehalose Biosynthesis in the Locust

Abstract

THE disaccharide trehalose was first identified as an important constituent of insect hæmolymph by Wyatt and Kalf¹ using silkmoth pupæ, and it has since been found in other insect species and in nematodes². Howden and Kilby³ showed that trehalose may occur in concentrations up to 2 per cent in the hæmolymph of the desert locust, Schistocerca gregaria Forsk., and isolated a crystalline sample from this source. Work with the migratory locust, Locusta migratoria ⁴, and the blowfly, Phormia regina ⁵, has shown that the concentration of trehalose falls sharply during flight, and it therefore appears that this sugar is an important soluble carbohydrate and energy reserve in insects. Treherne⁶ has shown that radioactive glucose introduced into the gut of Schistocerca rapidly gives rise to the appearance of radioactive trehalose in the hæmolymph, but nothing has been known hitherto as to the site or mode of formation of trehalose from glucose.