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At least 73 records · Page 4Linked to original sources
PubMed2006

Inhibition of type 2 isopentenyl diphosphate isomerase from Methanocaldococcus jannaschii by a mechanism-based inhibitor of type 1 isopentenyl diphosphate isomerase.

Type 2 isopentenyl diphosphate:dimethylallyl diphosphate isomerase (IDI-2, EC 5.3.3.2) is a flavoprotein, which requires FMN, NADPH, and Mg2+ for the activity to convert isopentenyl diphosphate to dimethylallyl diphosphate. For investigation of the reaction mechanism of IDI-2, 3,4-epoxy-3-methylbutyl diphosphate (EIPP), a mechanism-based inhibitor of type 1 IDI (IDI-1), was treated with the overexpressed IDI-2 (MjIDI) from methanogenic archaeon Methanocaldococcus jannaschii. EIPP showed the time- and concentration-dependent inhibition (KI; 56.5 mM, k(inact); 0.10 s(-1), k(inact)/KI; 1.76 s(-1)M(-1)) and the UV-vis spectrum of MjIDI after treatment with EIPP was apparently different from that of the untreated MjIDI. These results indicated that EIPP modified FMN through a covalent bond in the active site of MjIDI. The formed EIPP-FMN complex was separated from the reaction mixture and the spectrometric analysis of the complex suggested that the reduced form of FMN bound to EIPP at the N5 position. These results may suggest that the IDI-2 reaction is similar to IDI-1, which proceeds via carbocation-type intermediate.

Carbon-Carbon Double Bond Isomerases↗
PubMed1998

Substrate specificity of thermostable farnesyl diphosphate synthase with alkyl group homologs of isopentenyl diphosphate.

3-Alkyl group homologs of isopentenyl diphosphate were examined for the reactivity as substrates of the thermostable farnesyl diphosphate (FPP) synthase of Bacillus stearothermophilus. Even 3-n-propyl- and 3-n-butyl-but-3-enyl diphosphates, which are hardly acceptable by animal FPP synthases, are accepted by this bacterial enzyme as substrates to react with dimethylallyl- and geranyl diphosphates, yielding 7-methyl-3-n-propylocta-2,6-dienyl- and 7,11-dimethyl-3-n-propyldodeca-2,6,10-trienyl diphosphate, respectively.

Alkyl and Aryl Transferases↗
PubMed2000

Farnesyl diphosphate synthase. Altering the catalytic site to select for geranyl diphosphate activity.

Farnesyl diphosphate synthase (FPPase) catalyzes chain elongation of the C(5) substrate dimethylallyl diphosphate (DMAPP) to the C(15) product farnesyl diphosphate (FPP) by addition of two molecules of isopentenyl diphosphate (IPP). The synthesis of FPP proceeds in two steps, where the C(10) product of the first addition, geranyl diphosphate (GPP), is the substrate for the second addition. The product selectivity of avian FPPase was altered to favor synthesis of GPP by site-directed mutagenesis of residues that form the binding pocket for the hydrocarbon residue of the allylic substrate. Amino acid substitutions that reduced the size of the binding pocket were identified by molecular modeling. FPPase mutants containing seven promising modifications were constructed. Initial screens using DMAPP and GPP as substrates indicated that two of the substitutions, A116W and N144'W, strongly discriminated against binding of GPP to the allylic site. These observations were confirmed by an analysis of the products from reactions with DMAPP in the presence of excess IPP and by comparing the steady-state kinetic constants for the wild-type enzyme and the A116W and N114W mutants.

Alkyl and Aryl Transferases↗
PubMed1992

Isopentenyl-diphosphate isomerase: irreversible inhibition by 3-methyl-3,4-epoxybutyl diphosphate.

Isopentenyl-diphosphate:dimethylallyl-diphosphate isomerase (EC 5.3.3.2) catalyzes the 1,3-allylic rearrangement of the homoallylic substrate isopentenyl diphosphate (IPP) to its allylic isomer, dimethylallyl diphosphate (DMAPP). Incubation of yeast IPP isomerase with 3-methyl-3,4-epoxybutyl diphosphate (EIPP) resulted in a time-dependent first-order loss of activity characteristic of an active-site-directed irreversible process, where k2 = 0.63 +/- 0.10 min-1 and KI = 0.37 +/- 0.11 microM. A 1:1 covalent E-I complex was formed upon incubation with [1-14C]EIPP. The inhibited enzyme was treated with trypsin to give two radioactive fragments, which were purified by reversed-phase HPLC on a C18 column. The modified amino acid in each fragment was identified as C139 by sequencing the radiolabeled peptides. Incubation of IPP isomerase with [2,4,5-13C3]EIPP gave a 13C-labeled E-I complex. A 1H-13C heteronuclear multiquantum correlation spectrum had strong cross-peaks at 1.2/28 and 2.9/48 ppm, which we assigned to the labeled methyl group and C(4) methylene, respectively, of the inhibitor. In addition, a weak signal at 2.17/42 ppm may be from the C(2) methylene. Comparison of these chemical shifts with those of a synthetic adduct isolated from treatment of EIPP with cysteine indicates C139 attacks C(4) of EIPP to generate a thioether linkage between the enzyme and the inhibitor.

Amino Acid Sequence↗
PubMed1994

Identification of Cys139 and Glu207 as catalytically important groups in the active site of isopentenyl diphosphate:dimethylallyl diphosphate isomerase.

Isopentenyl diphosphate:dimethylallyl diphosphate isomerase (EC 5.3.3.2) catalyzes the antarafacial [1.3] allylic rearrangement of isopentenyl diphosphate (IPP) to its electrophilic allylic isomer dimethylallyl diphosphate (DMAPP). Active-site thiols at C138 and C139 were recently identified by covalent modification using active-site-directed irreversible inhibitors [Street, I. P., & Poulter, C. D. (1990) Biochemistry 29, 7531-7538; Lu, X. J., Christensen, D. J., & Poulter, C. D. (1992) Biochemistry 31, 9955-9960]. Kinetic studies were conducted with site-directed mutants of IPP isomerase (IPPIase) to evaluate the roles of these amino acids. C138S and C138V mutants were active catalysts with V/K values only 10-fold lower than that of wild-type IPPIase. In contrast, the C139S mutant was a poor catalyst, and the C139A and C139V mutants were inactive. Treatment of the C139S mutant with 3-(fluoromethyl)-3-butenyl diphosphate, an electrophilic active-site-directed irreversible inhibitor, resulted in inactivation of the enzyme by covalent modification of E207. The E207Q and E207V mutants were inactive, suggesting a role for the E207 carboxylate moiety in catalysis.

Amino Acid Sequence↗
PubMed2000

Geranylgeranyl diphosphate synthases from Scoparia dulcis and Croton sublyratus. cDNA cloning, functional expression, and conversion to a farnesyl diphosphate synthase.

cDNAs encoding geranylgeranyl diphosphate synthase (GGPPS) of two diterpene producing plants, Scoparia dulcis and Croton sublyratus, were isolated using the homology-based polymerase chain reaction method. Both cloned genes showed high amino acid sequence homology (60-70%) to other plant GGPPSs and contained highly conserved aspartate-rich motifs. The obtained clones were functionally expressed in Escherichia coli and showed sufficient GGPPS activity to catalyze the condensation of farnesyl diphosphate (FPP) and isopentenyl diphosphate to form geranylgeranyl diphosphate. To investigate the factor determining the product chain length of plant GGPPSs, S. dulcis GGPPS mutants in which either the small amino acids at the fourth and fifth positions before the first aspartate-rich motif (FARM) were replaced with aromatic amino acids or in which two additional amino acids in FARM were deleted were constructed. Both mutants behaved like FPPS-like enzymes and almost exclusively produced FPP when dimethylallyl diphosphate was used as a primer substrate, and failed to accept FPP as a primer substrate. These results indicate that both small amino acids at the fourth and fifth positions before FARM and the amino acid insertion in FARM play essential roles in product length determination in plant GGPPSs.

Alkyl and Aryl Transferases↗
PubMed2001

Geranylgeranyl diphosphate synthase from Scoparia dulcis and Croton sublyratus. Plastid localization and conversion to a farnesyl diphosphate synthase by mutagenesis.

cDNAs encoding geranylgeranyl diphosphate synthase (GGPPS) of two diterpene-producing plants, Scoparia dulcis and Croton sublyratus, have been isolated using the homology-based polymerase chain reaction (PCR) method. Both clones contained highly conserved aspartate-rich motifs (DDXX(XX)D) and their N-terminal residues exhibited the characteristics of chloroplast targeting sequence. When expressed in Escherichia coli, both the full-length and truncated proteins in which the putative targeting sequence was deleted catalyzed the condensation of farnesyl diphosphate and isopentenyl diphosphate to produce geranylgeranyl diphosphate (GGPP). The structural factors determining the product length in plant GGPPSs were investigated by constructing S. dulcis GGPPS mutants on the basis of sequence comparison with the first aspartate-rich motif (FARM) of plant farnesyl diphosphate synthase. The result indicated that in plant GGPPSs small amino acids, Met and Ser, at the fourth and fifth positions before FARM and Pro and Cys insertion in FARM play essential roles in determination of product length. Further, when a chimeric gene comprised of the putative transit peptide of the S. dulcis GGPPS gene and a green fluorescent protein was introduced into Arabidopsis leaves by particle gun bombardment, the chimeric protein was localized in chloroplasts, indicating that the cloned S. dulcis GGPPS is a chloroplast protein.

Alkyl and Aryl Transferases↗
PubMed1996

Mechanism-based inhibition of ribonucleoside diphosphate reductase from Corynebacterium nephridii by 2'-C-methyladenosine diphosphate.

The interaction of the adenosylcobalamin-dependent ribonucleoside diphosphate reductase of Corynebacterium nephridii with 2'-C-methyladenosine diphosphate (2'-C-methylADP) has been investigated in more detail [Ong, S. P., McFarlan, S. C., & Hogenkamp, H. P. C. (1993) Biochemistry 32, 11397-11404]. This nucleotide analog partitioned between normal reduction to 2'-deoxy-2'-C-methyladenosine diphosphate and decomposition to adenine, 2-methylene-3(2H)-4-methylfuranone, and presumably pyrophosphate. Reaction of the reduced enzyme with 2'-C-methylADP caused the development of a chromophore at 318 nm that is characteristic of the modification of the enzyme by the furanone [Harris, G., Ator, M., & Stubbe, J. (1984) Biochemistry 23, 5214-5225]. Incubation of [5'-3H2]-2'-C-methylADP with reduced reductase resulted in the covalent incorporation of the radiolabel into the protein and into aquocobalamin. A similar incubation of the enzyme, the labeled nucleotide analog, and dithiothreitol resulted in the formation of three radioactive hydrophilic compounds. Mass spectroscopic analysis of one of these compounds showed the presence of 2-methylene-3(2H)-4-methylfuranone. 2'-Deoxy-2'-C-methylADP is a very effective promoter of the tritium exchange reaction between [5'-3H2]adenosylcobalamin and the solvent, confirming that the exchange reaction is an integral part of the overall reduction. All these observations are consistent with the proposal that 2'-C-methylADP serves as a substrate and a mechanism-based inhibitor of the ribonucleotide reductase of C. nephridii, indicating that the enzyme is able to catalyze the conversion of the nucleotide analog to a 2'-deoxy-2'-C-methyl-3'-ketonucleotide that can collapse to the reactive 2-methylene-3(2H)-4-methylfuranone. Surprisingly, 2'-C-methylADP did not serve as either a substrate or an inhibitor of the ribonucleoside diphosphate reductase of Escherichia coli.

Adenosine Diphosphate↗
PubMed1993

2'-C-methyladenosine and 2'-C-methyluridine 5'-diphosphates are mechanism-based inhibitors of ribonucleoside diphosphate reductase from Corynebacterium nephridii.

The interaction of the adenyosylcobalamin-dependent ribonucleoside diphosphate reductase of Cornyebacterium nephridii with 2'-C-methyladenosine 5'-diphosphate (2'-MeADP) and 2'-C-methyluridine 5'-diphosphate (2'-MeUDP) has been investigated. The nucleotide analogs are converted to adenine and uracil, respectively, suggesting that they may be mechanism-based inhibitors. In addition, both analogs generate nucleotides with properties expected for the 2'-deoxy-2'-C-methylnucleotides. The nucleoside obtained after enzymatic dephosphorylation of the product formed from 2'-MeADP has been identified as 2'-deoxy-2'-C-methyladenosine by 1H NMR and mass spectroscopies. Adenine is the major product derived from 2'-MeADP, indicating that the degradation pathway predominates. During the reaction, the carbon-cobalt bond of the coenzyme is cleaved irreversibly to yield 5'-deoxyadenosine and cob(II)alamin. 2'-MeADP is a potent competitive inhibitor of the reduction of the purine nucleotides ADP and GDP, while 2'-MeUDP competitively inhibits the reduction of the pyrimidine nucleotides UDP and CDP. 2'-MeADP is a very effective promoter of the tritium exchange reaction between [5'-3H2]adenosylcobalamin and the solvent, indicating that the exchange reaction is an integral part of the overall reduction. All these observations are consistent with the reaction mechanism proposed by Stubbe and co-workers [Harris, G., Ashley, G. W., Robins, M. J., Tolman, R. L., & Stubbe, J. (1987) Biochemistry 26, 1895-1902 (1987); Stubbe, J. (1990) J. Biol. Chem. 265, 5329-5332] in which they suggest that the partitioning between reduction and inactivation occurs at the level of the 2'-deoxy-3'-ketoribonucleotide intermediate.

Adenosine Diphosphate↗
PubMed1977

[On the enzymatic breakdown of tripolyphosphate and diphosphate in comminuted meat. XII. Influence of the breakdown of tripolyphosphate and diphosphate on the water-holding-capacity of meat (author's transl)].

The increase in the water-holding capacity of salted minced bovine muscle caused by added diphosphate is maintained also after a complete enzymatic breakdown of the diphosphate. This effect is probably due to irreversible dissociation of actomyosin by DP in presence of NaCl.--An increase in water-holding capacity of minced salted bovine muscle after addition of tripolyphosphate occurs only if the tripolyphosphate is enzymatically hydrolysed to diphosphate. In contrast to diphosphate, tripolyphosphate apparently does not cause a dissociation of the actomyosin system.

Animals↗
PubMed2001

A fluorescent sensor of the phosphorylation state of nucleoside diphosphate kinase and its use to monitor nucleoside diphosphate concentrations in real time.

A sensor for purine nucleoside diphosphates in solution based on nucleoside diphosphate kinase (NDPK) has been developed. A single cysteine was introduced into the protein and labeled with the environmentally sensitive fluorophore, N-[2-(iodoacetamido)ethyl]-7-diethylaminocoumarin-3-carboxamide. The resultant molecule shows a 4-fold fluorescence increase when phosphorylated on His117; this phosphorylation is on the normal reaction pathway of the enzyme. The emission maximum of the phosphoenzyme is at 475 nm, with maximum excitation at 430 nm. The fluorescent phosphorylated NDPK is used to measure the amount of ADP and the unphosphorylated to measure ATP. The labeled protein is phosphorylated to > 90%, and the resultant molecule is stable on ice or can be stored at -80 degrees C. The fluorescence responds to the fraction of protein phosphorylated and so to the equilibrium between ADP plus NDPK approximately P and ATP plus NDPK. In effect, the sensor measures the ADP/ATP concentration ratio. The enzyme has a broad specificity for the purine of the nucleotides, so the sensor also can measure GDP/GTP ratios. The fluorescence and kinetic properties of the labeled protein are described. The binding rate constants of nucleotides are approximately 10(5) M(-1) s(-1), and the fluorescence change is at >200 s(-1) when the ADP concentration is >1 mM. Results are presented with two well-defined systems, namely, the kinetics of ADP release from myosin subfragment 1 and GDP release from the small G protein, human rho. The results obtained with this novel sensor agree with those from alternate methods and demonstrate the applicability for following micromolar changes in nucleoside diphosphate in real time.

Adenosine Diphosphate↗
PubMed1980

Fluoride, pyrophosphate, and base release from 2'-deoxy-2'-fluoronucleoside 5'-diphosphates by ribonucleoside-diphosphate reductase.

Ribonucleoside-diphsophate reductase from Escherichia coli catalyzes release of fluoride, inorganic pyrophosphate, and base from 2'-deoxy-2'-fluoronucleoside diphosphates. This reaction is accompanied by inactivation of the enzyme and an increase in absorbance at 314 nm of the inactivated protein. 2'-Deoxy-2'-fluoroadenosine 5'-diphosphate requires two turnovers per inactivation, whereas 2'-deoxy-2'-fluorocytidine 5'-diphosphate requires 100 turnovers per inactivation.

Adenosine Diphosphate↗
PubMed1984

The synthesis of a trisaccharide and a tetrasaccharide lipid intermediate. P1-dolichyl P2-[O-beta-D-mannopyranosyl-(1----4)-O-(2-acetamido-2-deoxy- beta-D-glucopyranosyl)-(1----4)-2-acetamido-2-deoxy-alpha-D- glucopyranosyl] diphosphate and P1-dolichyl P2-[O-alpha-D-mannopyranosyl-(1----3)-O-beta-D- mannopyranosyl-(1----4)-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)- (1----4)-2-acetamido-2-deoxy-alpha-D-glucopyranosyl] diphosphate.

Synthetic benzyl O-(2,3,4,6,-tetra-O-acetyl-beta-D-mannopyranosyl)-(1-4)- (2-acetamido-3,6-di-O-acetyl-2-deoxy-beta-D-glucopyranosyl)-(1-4)- 2-acetamido-3,6-di-O-benzyl-2-deoxy-alpha-D-glucopyranoside was converted, by catalytic hydrogenolysis of the benzyl groups, followed by treatment with acetyl chloride-hydrogen chloride and then "chloride-ion catalysis", into O-(2,3,4,6-tetra-O-acetyl- beta-D-mannopyranosyl)-(1-4)-O-(2-acetamido-3,6-di-O-acetyl-2-deoxy beta- D-glucopyranosyl)- (1-4)-2-methyl-(3,6-di-O-acetyl-1,2-dideoxy-alpha-D- glucopyrano)-[2,1-d]-2-oxazoline. This compound was phosphorylated by treatment with dibenzyl phosphate under strictly anhydrous conditions to give after catalytic hydrogenolysis, a peracetyl trisaccharide phosphate. This was coupled with P1-dolichyl P2-diphenyl diphosphate to give, after O-deacetylation, P1-dolichyl P2-[O- beta-D-mannopyranosyl- (1-4)-O-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)- (1-4)-2-acetamido-2-deoxy-alpha-D-glucopyranosyl] diphosphate, a trisaccharide "lipid intermediate". O-(2,3,4,6-Tetra-O-acetyl-alpha-D-mannopyranosyl)-(1-3)-O-(2,4,6-tri-O- acetyl-beta-D-mannopyranosyl)-(1-4)-O-(2-acetamido-3,6-di-O-acetyl-2- deoxy-beta- D-glucopyranosyl)- (1-4)-(2-acetamido-3,6-di-O-acetyl-2-deoxy-alpha-D-glucopyranosyl) phosphate, synthesized from O-alpha-D-mannopyranosyl-(1-3)-O-beta-D- mannopyranosyl-(1-4)-2-acetamido-2-deoxy-D-glucopyranose that had been isolated from mannosidosis urine was coupled with P1-dolichyl P2-diphenyl diphosphate to give, after O-deacetylation, P1-dolichyl P2-[O-alpha-D-mannopyranosyl- (1-3)-O-beta-D-mannopyranosyl-(1-4)-O-(2-acetamido-2-deoxy-beta-D- glucopyranosyl)-(1-4)-2-acetamido-2-deoxy-alpha-D-glucopyranosyl] diphosphate, a tetrasaccharide "lipid intermediate".

Chromatography, Thin Layer↗
PubMed1988

Different roles of the diphosphate moieties of allylic and homoallylic diphosphates in prenyltransferase reaction.

In contrast to the reactivity of geranyl methylene-diphosphonate in the reaction catalyzed by farnesyl diphosphate synthase, that of isopentenyl methylenediphosphonate showed an optimum at a more acidic pH than that of isopentenyl diphosphate, and it was inhibited by magnesium ions under certain conditions. These facts suggest that isopentenyl diphosphate is engaged in the enzyme reaction in the form of metal-free substrate contrary to the allylic substrate, which reacts in the form of metal-complexed substrate. Thus the diphosphate moieties of allylic and homoallylic substrates have different roles in the prenyltransferase reaction.

Animals↗
PubMed2002

Abietadiene synthase catalysis: conserved residues involved in protonation-initiated cyclization of geranylgeranyl diphosphate to (+)-copalyl diphosphate.

Abietadiene synthase catalyzes two sequential, mechanistically distinct cyclization reactions in the formation of a mixture of abietadiene double bond isomers as the committed step in resin acid biosynthesis. Each reaction is carried out at a separate active site residing in a structurally distinct domain, and the reactions are kinetically separable. The first cyclization reaction is initiated by protonation of the terminal double bond of the universal diterpene precursor, geranylgeranyl diphosphate. The pH dependence of the overall reaction is consistent with an acid-base catalytic mechanism, and a divalent metal ion plays a role in this reaction probably by binding the diphosphate moiety to assist in positioning the substrate for catalysis. A putative active site for the protonation-initiated cyclization was defined by modeling abietadiene synthase and locating the DXDD motif previously shown to be involved in this reaction. A number of charged and aromatic residues, which are highly conserved in mechanistically related diterpene cyclases, line the putative active site. Alanine substitutions were made for each of these residues, as were asparagine and glutamate substitutions for the aspartates of the DXDD motif. Kinetic evaluation confirmed the involvement of most of the targeted residues in the reaction, and analysis of mutational effects on the pH-activity profile and affinity for a transition state analogue suggested specific roles for several of these residues in catalyzing the cyclization of geranylgeranyl diphosphate to (+)-copalyl diphosphate. A functional role was also suggested for the cryptic insertional element found in abietadiene synthase and other diterpene synthases that carry out similar protonation-initiated cyclizations.

Amino Acid Motifs↗
PubMed1979

Studies on stringent control in a cell-free system. Regulation by guanosine-5'-diphosphate-3'-diphosphate of the synthesis of elongation factor Tu.

The biosynthesis of elongation factor Tu (EF-Tu) has been studied in a cell-free system with DNA of the transducing phage lambdarifd18 as a template. It was found that the synthesis of EF-Tu in this system was inhibited by about 60% in the presence of 0.3 to 0.6 mM guanosine-5'-diphosphate-3'-diphosphate (ppGpp). The syntheses of several ribosomal proteins encoded in this template, i.e. L1, L10, L11, and L7/L12, were also depressed, whereas those of phage lambda proteins were rather enhanced by the addition of ppGpp. By separating the reaction into two steps, i.e., transcription and translation, the effect of ppGpp was shown to occur at the level of transcription. Several analogs, such as guanosine-5'-diphosphate-3'-monophosphate (ppGp) and guanosine-5'-diphosphate (ppG), were without effect. The formation of mRNA for EF-Tu was assessed directly by specific hybridization with pTUA1 DNA carrying tufA gene. The results clearly indicated that the synthesis of tufB . MRNA was severely and selectively inhibited by ppGpp.

Bacteriophage lambda↗
PubMed2006

Maize cDNAs expressed in endosperm encode functional farnesyl diphosphate synthase with geranylgeranyl diphosphate synthase activity.

Isoprenoids are the most diverse and abundant group of natural products. In plants, farnesyl diphosphate (FPP) and geranylgeranyl diphosphate (GGPP) are precursors to many isoprenoids having essential functions. Terpenoids and sterols are derived from FPP, whereas gibberellins, carotenoids, casbenes, taxenes, and others originate from GGPP. The corresponding synthases (FPP synthase [FPPS] and GGPP synthase [GGPPS]) catalyze, respectively, the addition of two and three isopentenyl diphosphate molecules to dimethylallyl diphosphate. Maize (Zea mays L. cv B73) endosperm cDNAs encoding isoprenoid synthases were isolated by functional complementation of Escherichia coli cells carrying a bacterial gene cluster encoding all pathway enzymes needed for carotenoid biosynthesis, except for GGPPS. This approach indicated that the maize gene products were functional GGPPS enzymes. Yet, the predicted enzyme sequences revealed FPPS motifs and homology with FPPS enzymes. In vitro assays demonstrated that indeed these maize enzymes produced both FPP and GGPP and that the N-terminal sequence affected the ratio of FPP to GGPP. Their functionality in E. coli demonstrated that these maize enzymes can be coupled with a metabolon to provide isoprenoid substrates for pathway use, and suggests that enzyme bifunctionality can be harnessed. The maize cDNAs are encoded by a small gene family whose transcripts are prevalent in endosperm beginning mid development. These maize cDNAs will be valuable tools for assessing the critical structural properties determining prenyl transferase specificity and in metabolic engineering of isoprenoid pathways, especially in cereal crops.

Amino Acid Motifs↗