Blood Trehalose and Fat-Body Glycogen in the Silkworm, Bombyx mori

SINCE the report by Wyatt and Kalf 1 that trehalose is the principal carbohydrate in, silkworm blood, attention has been paid to the biosynthetic process of this disaccharide in insects. Treherne 2 showed that trehalose labelled with carbon-14 is synthesized from labelled glucose, fructose and mannose in the locust, Schistocerca , and Candy and Kilby 3 demonstrated with this insect that the fat-body participates in the biosynthesis of trehalose, where adenosine triphosphate and uridine diphosphate glucose are required as co-factors for the enzymatic reactions involved. However, there are no publications dealing extensively with the correlation between in vivo formation of trehalose and various carbohydrates ingested by insects. As for the biosynthesis of glycogen, such a correlation has been elucidated, to some extent, with the fat body and other tissues of insects 4 .