Artificial substrates of medium-chain elongating enzymes, hexaprenyl- and heptaprenyl diphosphate synthases.
We examined the reactivity of 3-alkyl group homologues of farnesyl diphosphate or isopentenyl diphosphate for medium-chain prenyl diphosphate synthases, hexaprenyl diphosphate- or heptaprenyl diphosphate synthase. But-3-enyl diphosphate, which lacks the methyl group at the 3-position of isopentenyl diphosphate, condensed only once with farnesyl diphosphate to give E-norgeranylgeranyl diphosphate by the action of either enzyme. However, norfarnesyl diphosphate was never accepted as an allylic substrate at all. 3-Ethylbut-3-enyl diphosphate also reacted with farnesyl diphosphate giving a mixture of (all-E)-3-ethyl-7,11,15-trimethylhexadeca-2,6,10,14-tetraenyl- and (all-E)-3,7-diethyl-11,15,19-trimethylicosa-2,6,10,14,18-pentaenyl diphosphates by hexaprenyl diphosphate synthase. On the other hand, heptaprenyl diphosphate synthase reaction of 3-ethylbut-3-enyl diphosphate with farnesyl diphosphate gave only (all-E)-3-ethyl-7,11,15-trimethylhexadeca-2,6,10,14-tetraenyl diphosphate.
Nagaki
M
M
Department of Materials Science and Technology, Faculty of Science and Technology, Hirosaki University, 3 Bunkyo-cho, Hirosaki, 036-8561, Aomori, Japan. nagaki@cc.hirosaki-u.ac.jp
Kimura
K
K
Kimura
H
H
Maki
Y
Y
Goto
E
E
Nishino
T
T
Koyama
T
T
D019883:Alkyl and Aryl Transferases / Q000378:metabolism*; D011756:Diphosphates / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism*; D013379:Substrate Specificity
D011756:Diphosphates; D019883:Alkyl and Aryl Transferases; C024844:trans-hexaprenyltranstransferase; C036826:trans-pentaprenyltranstransferase