Inhibition of Carotene Biosynthesis in Cell Extracts of Phycomyces blakesleeanus
نویسندگان
چکیده
Cell extracts o f the Cl 15 (^-carotene-accumulating) strain o f Phycomyces blakesleeanus were incubated with either [2-l4C]MVA or [1-I4C]IPP and a range o f possible inhibitors of carotenogenesis, including bleaching herbicides, biphenyl com pounds and geranylacetone. Several o f these compounds were potent inhibitors o f /7-carotene formation and caused the accumulation o f phytoene. No other carotenes were found to accumulate, in vitro. The structures o f these inhibi tors, compared to that of phytoene, suggest that they affect the enzym ic activity o f “phytoene dehydrogenase”, possibly by com petitive inhibition.
منابع مشابه
Carotene biosynthesis in fungi.
Studies on Neurospora crassa and mutants of Phycomyces blakesleeanus have led to a reappraisal of a number of important aspects of carotene biosynthesis. Results obtained from structural investigations, from inhibitor studies and from the use of labelled substrates with carotenogenic extracts of fungal mutants are discussed in the contexts of the stereochemistry, isomerization and dehydrogenati...
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