Insects carbohydrate metabolism

Studies of the carbohydrate metabolism of T. cruzi (21) have shown that phos-phoenolpyruvate serves as the acceptor of the primary COj-fixation reaction. This resulted in the formation of oxaloacetate and malate and the excretion of succinate. The central role of PEPCK in energy metabolism in insect-stage trypanosomatids has been illustrated in the case of T. cruzi epimastigotes, using 3-mercaptopicolinic aeid, a powerful inhibitor of this enzyme (22). Inhibition led to a twofold reduction in the anaerobic production of succinate and a similar decrease in glucose consumption, while the production of alanine, via the transamination of pyruvate, increased threefold. 

Hartmann T, Ober D (2000) Biosynthesis and Metabolism of Pyrrolizidine Alkaloids in Plants and Specialized Insect Herbivores. 209. 207-243 Haseley SR, Kamerling JP, Vliegenthart JFG (2002) Unravelling Carbohydrate Interactions with Biosensors Using Surface Plasmon Resonance (SPR) Detection. 218 93-114... 

Adipokinetic hormones control metabolism of insects during long-distance flight.359 363 In the migratory locust these hormones consist of a pair of related octapeptides and a decapeptide (Table 30-5). The hormones stimulate triacylglycerol lipase in the insects fat bodies, induce release of carbohydrates from body stores, and affect many other aspects of metabolism.363 Insects also have hormones of the insulin family, proteins consisting of disulfide-linked A and B chains as in insulin. The silkworm Bombyx mori has 38 genes for the insulinlike bombyxins, which are synthesized in the brain.364... 

The most widely recognized physiological action of the insect AKH/HGHs is to mobilize lipids or carbohydrates from fat body reserves for use as energy substrates by peripheral tissues. In Leptinotarsa decemlineata, proline is the main substrate for flight muscle metabolism (16), and Lom-AKH-I promotes fat body proline synthesis... 

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