Metabolism of plastid terpenoids: lycopene cyclization by Capsicum chromoplast membranes

摘要: Abstract The cyclization of lycopene to β,β-carotene (β-carotene) was studied using chromoplast membranes prepared from Capsicum fruits. enzymic activity is tightly bound the and, under optimal conditions, cyclized β-carotene without accumulation intermediate β,ψ-carotene (γ-carotene). In this system, no formation (6,R)-β,ϵ-carotene (α-carotene) occurs. pH for 6.8. Nucleotide cofactors are not required activity. stimulated in presence Tween 80 contrast inhibitory effect Triton X-100. Thiol reagents such as mersalyl, N-ethylmaleimide and p-chloromercuribenzoate strongly inhibit β-carotene. Octyldiethylamine dodecyl diethylamine potent inhibitors cyclase membranes.