Submitted to: American Chemical Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: August 28, 2001
Publication Date: N/A
Technical Abstract: One major difference between parasitic nematodes and plant or mammalian hosts is that nematodes possess a nutritional requirement for sterol, resulting from their inability to biosynthesize sterols de novo. Comparative examination of steroid biochemistry within several plant-parasitic and free-living nematodes has revealed that most species dealkylate phytosterols at C-24 and modify the sterol nucleus. The potential of disrupting the nematode life cycle by specific inhibitors of nematode steroid biochemistry has been demonstrated in several nematode species. Some nematode species are capable of attaching a methyl group to the ring system of sterols at C-4; this transformation appears to be unique to nematodes. Rigorous experiments have failed to demonstrate the biosynthesis of insect molting hormones (ecdysteroids) in nematodes. Extracts of some (but not all) nematodes contain material comigrating with ecdysone during TLC but actually consisting of a series of monoglucosylceramides with an unusual, branched sphingoid base.