the fluoro substitution at the C6 position of farnesyl diphosphate has negligible effects on enzyme binding, substrate orientation, diphosphate ionization, and the initial 1,10 ring closure catalyzed by TEAS
about 79% of hydrocarbon product, plus about 6% of (-)-4-epi-eremophilene, 3.6% of (+)-germacrene A and 22 hydrocarbons contributing about 12% of TEAS sesquiterpene products. The pathway to the by-products starts with a 1,6 cyclization of the (Z,E)-farnesyl cation, followed by a 1,2 hydride shift leading to a syn-6,10 ring closure which generates an acoradilyl cation. Elimination of a proton from either C12 or C13 of the isopropylidene tail of the acoradilyl cation readily explains the formation of ?-acoradiene. Alternatively, a 2,11 ring closure followed by elimination of a proton at C2 is the likely pathway to (-)-alpha-cedrene. A 3,11 ring closure of the acoradilyl cation is the most common event, based on the relative abundance of isomerization products observed, and is followed by Wagner-Meerwein rearrangement and proton elimination from C15 to produce isoprezizaene, the dominant (Z,E)-farnesyl cation-derived product
reaction proceeds via geracrene A as an intermediate. Proton donation by residue Y520 is responsible for the activation of germacrene A to a eudesmane cation
no constitutive expression of EAS and capsidiol accumulation in shoots of rosette plants, but accumulation of transcripts can be induced in shoots by feeding of the tobacco hornworm, Manduca sexta
no constitutive expression of EAS and capsidiol accumulation in shoots of rosette plants, but accumulation of transcripts can be induced in shoots by feeding of the tobacco hornworm, Manduca sexta
no constitutive expression of EAS and capsidiol accumulation in shoots of rosette plants, but accumulation of transcripts can be induced in shoots by feeding of the tobacco hornworm, Manduca sexta
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
Crystallization/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
to 2.2-2.8 A resolution, of TEAS alone and in complexes with two different substrate analogs. TEAS consists entirely of alpha-helices and short connecting loops and turns, and is organized into two structural domains. Two Mg2+ ions are coordinated on opposite sides of the entrance to the active site pocket, and constitute a diphosphate binding site. Asp301 coordinates a Mg2+ in the native TEAS structure, and the side chain carboxyl of Glu379 provides a longer range interaction. Asp305 provides an additional coordination bond in the enzyme with substrate analogs bound. Asp301 and Asp305 are part of a -DDXXD- sequence. Asp301 directly contacts Mg2+, whereas Asp302 demonstrates no direct metal coordination. The side chains of Asp444, Thr448, Glu452, and one water molecule the second coordinate Mg2+. In the native TEAS structure, the A-C and J-K loops and the residues NH2-terminal of residue 36 are disordered
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
EXPRESSION
ORGANISM
UNIPROT
LITERATURE
accumulation of transcripts can be induced in shoots by feeding of the tobacco hornworm, Manduca sexta; accumulation of transcripts can be induced in shoots by feeding of the tobacco hornworm, Manduca sexta; accumulation of transcripts can be induced in shoots by feeding of the tobacco hornworm, Manduca sexta
heterologous expression of EAS in transgenic rice does not interfere with the activities of endogenous squalene synthase or farnesyl diphosphatase. The induction of EAS enzyme activity is accompanied by an increase in EAS mRNA when challenged by the elicitor. The EAS ectopic expression in transgenic rice plants results in the synthesis of 5-epi-aristolochene in vivo upon elicitor treatment
construction of fusion proteins with farnesyl diphosphate synthase FPPS from Artemisia annua. The fusion enzymes produce epi-aristolochene from isopentenyl diphosphate through a coupled reaction. The Km values of FPPS and eAS for isopentenyl diphosphate and farnesyl diphosphate, respectively, are essentially the same for the single and fused enzymes. The bifunctional enzymes show a more efficient conversion of isopentenyl diphosphate to epi-aristolochene than the corresponding amount of single enzymes
engineering of a thermostable mutant by SCADS algorithm to suggest mutations based on side-chain interactions consistent with the nearby protein backbone, neighboring sidechains, and the local environment, and by replacement of solvent-exposed hydrophobic residues and the addition of salt bridges on the surface of the mutant enzyme. Contrary to wild-type, mutant is still active to 65°C but produces additional sesquiterpene products
method for the recovery of full-length cDNAs from predicted terpene synthase genes containing introns. The approach utilizes Agrobacterium-mediated transient expression coupled with a reverse transcription-polydeoxyribonucleotide chain reaction assay to facilitate expression cloning of processed transcripts. Subsequent expression of intronless cDNAs in a suitable prokaryotic host provides for direct functional testing of the encoded gene product
expression system in Escherichia coli, highest expression level after 3 h induction with low concentration of IPTG and incubation at 27°C. Epiaristolochene synthase protein constitutes up to 35% of total Escherichia coli proteins
construction of fusion proteins with farnesyl diphosphate synthase FPPS from Artemisia annua. The fusion enzymes produce epi-aristolochene from isopentenyl diphosphate through a coupled reaction. The Km values of FPPS and eAS for isopentenyl diphosphate and farnesyl diphosphate, respectively, are essentially the same for the single and fused enzymes. The bifunctional enzymes show a more efficient conversion of isopentenyl diphosphate to epi-aristolochene than the corresponding amount of single enzymes
Lee, H.; Lee, D.; Ha, S.; Jang, S.; Lee, I.; Ryu, S.; Back, K.
The characterization of transgenic rice plants expressing a pepper 5-epi aristolochene synthase, the first committed step enzyme for capsidiol synthesis in isoprenoid pathway