Bees, sterol metabolism

Bacteria, synthesis, 65 Bacteriohopane skeleton formation, pentacyclic C35, See Pentacyclic C35 bacteriohopane skeleton formation Bees, sterol metabolism, 131,132/133 Beetles, sterol metabolism, 133-134... 

Some of this variability in sterol metabolism capabilities could well be exploited in developing new selective control methodology. As an example, it was found that certain inhibitors that block conversion of C28 and C29 phytosterols to cholesterol and adversely affect growth and development in Lepidoptera and species of other orders that dealkylate, had no effect on the honey bee, which is unable to dealkylate 58). Any technology that would limit the availability of utilizable sterol in a pest insect could provide a useful addition to our arsenal of weapons to use against insect pests. 

Hymenoptera. While examining the effects of various dietary sterols on brood production in honey bees. Apis mellifera, we discovered that the honey bee utilized dietary C28 and (igg phytosterols unchanged (25,26). Regardless of the dietary sterol added to a chemically-deTTneJ diet, or even with no sterol added, 24-methylenecholesterol was always the major sterol of the next generation of bees, and sitosterol and isofucosterol were also present in appreciable amounts. Detailed studies with either radiolabeled campesterol, sitosterol, or 24-methy1 enecholesterol added to the artificial diet provided no evidence for the metabolism of any of these phytosterols to cholesterol or other sterols (27). 

More recently, the utilization and metabolism of dietary sterols in the honey bee. Apis mellifera, has been examined in detail utilizing a chemically defined diet (24). Experiments with radiolabeled sterols demonstrated unequivocally that this important beneficial insect is unable to remove C-24 alkyl groups from the sterol side chain (25). The nurse bees have the ability to selectively transfer certain sterols to the brood food they produce for the larvae. As a result, 24>methylenecholesterol is the major sterol found in the prepupae regardless of the dietary sterol included in the diet. Even when no sterol was added to the diet of the nurse bees, 24-methylenecholesterol was the major sterol identified in the prepupal sterols (26). 

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