Showing papers on "Farnesyl pyrophosphate published in 2004"
TL;DR: Crystal structures of substrate and bisphosphonate complexes of FPPS provide a structural template for the design of novel inhibitors that may prove useful for the treatment of osteoporosis and other clinical indications including cancer.
256 citations
TL;DR: This review focuses on C-10 mono-, C-15 sesqui-, and C-20 diterpenes, and the diverse functions of these molecules, including their ability to regulate expression of the β-HMG-CoA reductase and Ras-related proteins.
Abstract: The isoprenoid biosynthetic pathway is the source of a wide array of products. The pathway has been highly conserved throughout evolution, and isoprenoids are some of the most ancient biomolecules ever identified, playing key roles in many life forms. In this review we focus on C-10 mono-, C-15 sesqui-, and C-20 diterpenes. Evidence for interconversion between the pathway intermediates farnesyl pyrophosphate and geranylgeranly pyrophosphate and their respective metabolites is examined. The diverse functions of these molecules are discussed in detail, including their ability to regulate expression of the β-HMG-CoA reductase and Ras-related proteins. Additional topics include the mechanisms underlying the apoptotic effects of select isoprenoids, antiulcer activities, and the disposition and degradation of isoprenoids in the environment. Finally, the significance of pharmacological manipulation of the isoprenoid pathway and clinical correlations are discussed.
214 citations
TL;DR: Combinations of some terpenes or S-farnesylthiosalicylic acid tested in this work with other antimalarial drugs, like fosmidomycin, could be a new strategy for the treatment of malaria.
Abstract: Development of new drugs is one of the strategies for malaria control The biosynthesis of several isoprenoids in Plasmodium falciparum was recently described Interestingly, some intermediates and final products biosynthesized by this pathway in mammals differ from those biosynthesized in P falciparum These facts prompted us to evaluate various terpenes, molecules with a similar chemical structure to the intermediates of the isoprenoids pathway, as potential antimalarial drugs Different terpenes and S -farnesylthiosalicylic acid were tested on cultures of the intraerythrocytic stages of P falciparum , and the 50% inhibitory concentrations for each one were found: farnesol, 64 μM; nerolidol, 760 nM; limonene, 122 mM; linalool, 028 mM; and S -farnesylthiosalicylic acid, 14 μM All the terpenes tested inhibited dolichol biosynthesis in the trophozoite and schizont stages when [1-( n )- 3 H]farnesyl pyrophosphate triammonium salt ([ 3 H]FPP) was used as precursor Farnesol, nerolidol, and linalool showed stronger inhibitory activity on the biosynthesis of the isoprenic side chain of the benzoquinone ring of ubiquinones in the schizont stage Treatment of schizont stages with S -farnesylthiosalicylic acid led to a decrease in intensity of the band corresponding a p21 ras protein The inhibitory effect of terpenes and S -farnesylthiosalicylic acid on the biosynthesis of both dolichol and the isoprenic side chain of ubiquinones and the isoprenylation of proteins in the intraerythrocytic stages of P falciparum appears to be specific, because overall protein biosynthesis was not affected Combinations of some terpenes or S -farnesylthiosalicylic acid tested in this work with other antimalarial drugs, like fosmidomycin, could be a new strategy for the treatment of malaria
144 citations
TL;DR: It is demonstrated that simvastatin inhibited RhoA function by preventing its association with the plasma membrane and hence, its interaction with downstream effectors required for cell proliferation, suggesting that statins may have an important role in preventing adverse myocardial remodeling associated with cardiac myofibroblast proliferation.
Abstract: Objective : Adverse atrial and ventricular myocardial remodeling is characterized by fibrosis, myocyte death or hypertrophy and fibroblast proliferation. HMG-CoA reductase inhibitors (statins) are widely prescribed cholesterol-lowering drugs that also appear to have beneficial effects on myocardial remodeling. Although statins are known to reduce myocyte hypertrophy, their effect on cardiac fibroblast proliferation is unknown. The purpose of this study was to investigate the effects of simvastatin on human atrial myofibroblast proliferation. Methods : Cardiac myofibroblasts were cultured from biopsies of human right atrial appendage. Proliferation was quantified by cell counting and cell cycle progression determined by immunoblotting for Cyclin A. The expression, activation and intracellular localization of RhoA were investigated using immunoblotting and immunocytochemistry. Results : Simvastatin (0.1–1.0 μmol/l) inhibited serum-induced myofibroblast proliferation in a concentration-dependent manner at a point upstream of Cyclin A expression. These effects were reversed by mevalonate or geranylgeranyl pyrophosphate (GGPP), but not squalene or farnesyl pyrophosphate (FPP), indicating a mechanism involving inhibition of Rho-family GTPases and independent of cholesterol synthesis. The effects of simvastatin were mimicked by inhibiting Rho geranylgeranylation or Rho-kinase activation. Furthermore, we demonstrated that simvastatin inhibited RhoA function by preventing its association with the plasma membrane and hence, its interaction with downstream effectors required for cell proliferation. Conclusions : Simvastatin reduced proliferation of cultured human atrial myofibroblasts independently of cholesterol synthesis via a mechanism involving inhibition of RhoA geranylgeranylation. Statins may therefore have an important role in preventing adverse myocardial remodeling associated with cardiac myofibroblast proliferation.
132 citations
TL;DR: The data suggest that the 3-hydroxy-3-methylglutaryl-coenzyme-A (HMG-CoA)/GG-PP/Rho/ Rho-kinase pathway mediates CAM-DR and that targeting this pathway may improve the efficacy of antimyeloma therapies by reduction of Cam-DR.
130 citations
TL;DR: Ris is a promising lead compound for the development of new drugs against T. cruzi and has a variety of effects on cellular ultrastructure, including mitochondrial swelling, disorganisation of other organelles, such as reservosomes and the kinetoplast, together with the appearance of autophagic vesicles and progressive vacuolization of the cytoplasm.
85 citations
TL;DR: The vasculoprotective effects of hydroxy-3-methylglutaryl (HMG)-CoA reductase inhibitors (statins) correlate with cholesterol lowering as discussed by the authors.
72 citations
TL;DR: The first structure of long chain C40-OPPs from Thermotoga maritima has been determined to 2.28-Å resolution and the new structure of the trans-type OPPs, together with the recently determined cis-type UPPs significantly extends the authors' understanding on the biosynthesis of longChain polyprenyl molecules.
70 citations
TL;DR: The inhibition of Fc receptor–mediated phagocytosis of lovastatin is related to its effect on cholesterol biosynthesis rather than its effecton the formation of isoprenoids.
Abstract: Objectives—An inflammatory response to altered lipoproteins that accumulate in the arterial wall is a major component of the pathogenesis of atherosclerosis. Statins reduce plasma levels of low-density lipoprotein (LDL) and are effective treatments for atherosclerosis. It is hypothesized that they also modulate inflammation. The aim of this study was to examine whether lovastatin inhibits macrophage inflammatory processes and clarify its mechanism of action. Methods and Results—We examined the effects of statins on phagocytosis of antibody-coated red blood cells by cultured human monocytes and mouse peritoneal macrophages. Lovastatin, simvastatin, and zaragozic acid, a squalene synthase inhibitor, blocked Fc receptor–mediated phagocytosis by cultured human monocytes and mouse peritoneal macrophages. The inhibitory effect of lovastatin on Fc receptor–mediated phagocytosis was prevented completely by addition of mevalonate, farnesyl pyrophosphate, LDL, or cholesterol to the culture medium. The inhibitory effect of zaragozic acid was reversed by addition of LDL, but not by the addition of geranylgeranyl pyrophosphate, to the medium. In addition, the effect of lovastatin on phagocytosis is a function of cell activation because treatment of cells with tumor necrosis factor- or lipopolysaccharide prevented inhibition of phagocytosis by lovastatin. Conclusions—The inhibition of Fc receptor–mediated phagocytosis of lovastatin is related to its effect on cholesterol biosynthesis rather than its effect on the formation of isoprenoids. (Arterioscler Thromb Vasc Biol. 2004; 24:2051-2056.)
69 citations
TL;DR: It is proposed that molecules might interact each-other to form a highly matched free-radical-transfer chain, whose malfunctioning might be involved in statin toxicity and neurodegenerative diseases.
Abstract: Dolichol is a polyprenol compound broadly distributed in membranes, biosynthetized by the general isoprenoid pathway from acetate via mevalonate and farnesyl pyrophosphate. Dolichol lays inside the membrane between the two leaflets of the lipid bilayer very close to the tail of phospholipid fatty acids. No definite catabolic pathways for this molecule have yet been identified. Evidence is produced that dolichol levels increase dramatically with increasing age; that anti-ageing caloric restriction retards this age-associated change; that dolichol may act as a radical scavenger of peroxidized lipids belonging to the cell membranes. In view of the polyunsaturated fatty acids (PUFA), dolichol and Vitamin E location and stechiometry, it is proposed that molecules might interact each-other to form a highly matched free-radical-transfer chain, whose malfunctioning might be involved in statin toxicity and neurodegenerative diseases.
57 citations
TL;DR: The crystal structure of the apo‐enzyme from Escherichia coli and the structure of UPPs in complex with sulfate ions (resembling pyrophosphate of substrate), Mg2+, and two Triton molecules (product‐like) are solved.
Abstract: Undecaprenyl pyrophosphate synthase (UPPs) catalyzes eight consecutive condensation reactions of farnesyl pyrophosphate (FPP) with isopentenyl pyrophosphate (IPP) to form a 55-carbon long-chain product. We previously reported the crystal structure of the apo-enzyme from Escherichia coli and the structure of UPPs in complex with sulfate ions (resembling pyrophosphate of substrate), Mg2+, and two Triton molecules (product-like). In the present study, FPP substrate was soaked into the UPPs crystals, and the complex structure was solved. Based on the crystal structure, the pyrophosphate head group of FPP is bound to the backbone NHs of Gly29 and Arg30 as well as the side chains of Asn28, Arg30, and Arg39 through hydrogen bonds. His43 is close to the C2 carbon of FPP and may stabilize the farnesyl cation intermediate during catalysis. The hydrocarbon moiety of FPP is bound with hydrophobic amino acids including Leu85, Leu88, and Phe89, located on the α3 helix. The binding mode of FPP in cis-type UPPs is apparently different from that of trans-type and many other prenyltransferases which utilize Asprich motifs for substrate binding via Mg2+. The new structure provides a plausible mechanism for the catalysis of UPPs.
TL;DR: It is concluded that livers with PPARα activation are transcriptionally geared towards fatty acid combustion.
Abstract: Peroxisome proliferator-activated receptor alpha (PPARalpha) is important in the induction of cell-specific pleiotropic responses, including the development of liver tumors, when it is chronically activated by structurally diverse synthetic ligands such as Wy-14,643 or by unmetabolized endogenous ligands resulting from the disruption of the gene encoding acyl coenzyme A (CoA) oxidase (AOX). Alterations in gene expression patterns in livers with PPARalpha activation were delineated by using a proteomic approach to analyze liver proteins of Wy-14,643-treated and AOX(-/-) mice. We identified 46 differentially expressed proteins in mouse livers with PPARalpha activation. Up-regulated proteins, including acetyl-CoA acetyltransferase, farnesyl pyrophosphate synthase, and carnitine O-octanoyltransferase, are involved in fatty acid metabolism, whereas down-regulated proteins, including ketohexokinase, formiminotransferase-cyclodeaminase, fructose-bisphosphatase aldolase B, sarcosine dehydrogenase, and cysteine sulfinic acid decarboxylase, are involved in carbohydrate and amino acid metabolism. Among stress response and xenobiotic metabolism proteins, selenium-binding protein 2 and catalase showed a dramatic approximately 18-fold decrease in expression and a modest approximately 6-fold increase in expression, respectively. In addition, glycine N-methyltransferase, pyrophosphate phosphohydrolase, and protein phosphatase 1D were down-regulated with PPARalpha activation. These observations establish proteomic profiles reflecting a common and predictable pattern of differential protein expression in livers with PPARalpha activation. We conclude that livers with PPARalpha activation are transcriptionally geared towards fatty acid combustion.
Patent•
10 Jun 2004TL;DR: A carotenogenic biosynthetic gene cluster has been isolated from Panteoa agglomerans strain DC404, wherein the genetic organization of the cluster is crtE-idi-crtY-CRTI-crTB-CRtZ as mentioned in this paper, and the genes contained within this cluster encode geranylgeranyl pyrophosphate (GGPP) synthetase (CrtE), isopentenyl pyrophophosphate isomerase (Idi), lycopene cyclase(CrtY), phytoene
Abstract: A unique carotenogenic biosynthetic gene cluster has been isolated from Panteoa agglomerans strain DC404, wherein the genetic organization of the cluster is crtE-idi-crtY-crtI-crtB-crtZ. The genes contained within this cluster encode geranylgeranyl pyrophosphate (GGPP) synthetase (CrtE), isopentenyl pyrophosphate isomerase (Idi), lycopene cyclase (CrtY), phytoene desaturase (CrtI), phytoene synthase (CrtB), and β-carotene hydroxylase (CrtZ). The gene cluster, genes and their products are useful for the conversion of farnesyl pyrophosphate to carotenoids. Vectors containing those DNA segments, host cells containing the vectors and methods for producing those enzymes by recombinant DNA technology in transformed host organisms are disclosed.
TL;DR: This work analyzed the actions of zoledronic acid and doxorubicin on PC‐3 prostate cancer cells using both continuous and pulsatile exposures for up to three consecutive days.
Abstract: OBJECTIVES. We analyzed the actions of zoledronic acid (10–250 mM) and doxorubicin (10– 250 nM) on PC-3 prostate cancer cells using both continuous (48–96 hr) and pulsatile exposures (15 min/day for up to three consecutive days). RESULTS. The proliferation of PC-3 cells was inhibited by either continuous or pulsatile exposures of zoledronic acid in a dose-dependent manner. In contrast, pulsatile exposures of doxorubicin failed to inhibit the growth of PC-3 cells. In addition, the inhibition of PC-3 cells by zoledronic acid was partially neutralized by exogenous administration of geranylgeranyl pyrophosphate (GGPP), however, not by farnesyl pyrophosphate (FPP). Furthermore, exogenous administration of transforming growth factor beta 1 (TGF-b1), interleukin 6 (IL-6), basic fibroblast growth factor (bFGF), and more potently, insulin-like growth factor 1 (IGF-1) inhibited the doxorubicin-induced apoptosis of PC-3 cells. Under identical experimental conditions, these growth factors failed to alter the cytotoxicity of PC-3 cells induced by zoledronic acid. CONCLUSIONS. These data suggest that (i) repetitive and pulsatile (15 min/day) exposure to zoledronic acid inhibited the growth of PC-3 cells, (ii) this anticancer action of zoledronic acid was partially mediated by the attenuation of GGPP production, and (iii) bone microenvironment-related growth factors do not alter the anticancer actions of zoledronic acid on PC-3 cells. Prostate 59: 120–131, 2004. # 2003 Wiley-Liss, Inc.
TL;DR: Results indicate that the farnesyl pyrophosphate analogue penetrates the cells as an intact pyroph phosphate and that it does so at a biologically relevant concentration.
Abstract: New fluorescent analogues of farnesol and geranylgeraniol have been prepared and then converted to the corresponding pyrophosphates. These analogues incorporate anthranylate or dansyl-like groups anchored to the terpenoid skeleton through amine bonds that would be expected to be relatively stable to metabolism. After addition of the alcohols or the pyrophosphates to the culture medium, their fluorescence is readily observed inside a human-derived leukemia cell line. Enzyme assays have revealed that the farnesyl pyrophosphate analogue is an inhibitor of FTase, while the corresponding alcohol is not. These results, together with Western blot analyses of cell lysates, indicate that the farnesyl pyrophosphate analogue penetrates the cells as an intact pyrophosphate and that it does so at a biologically relevant concentration.
TL;DR: The X-ray structure of OPPs from Thermotoga maritima is reported and sequentially mutated the large amino acids, including F132, L128, I123, and D62, to Ala underneath the tunnel, indicating that the substituted larger residues interfere with the substrate chain elongation.
Abstract: Octaprenyl pyrophosphate synthase (OPPs) catalyzes consecutive condensation reactions of farnesyl pyrophosphate (FPP) with five molecules of isopentenyl pyrophosphate (IPP) to generate C40 octaprenyl pyrophosphate (OPP) which constitutes the side chain of menaquinone. We have previously reported the X-ray structure of OPPs from Thermotoga maritima, which is composed entirely of α-helices joined by connecting loops and is arranged with nine core helices around a large central cavity [Guo, R. T., Kuo, C. J., Ko, T. P., Chou, C. C., Shr, R. L., Liang, P. H., and Wang, A. H.-J. (2004) J. Biol. Chem. 279, 4903−4912]. A76 and S77 are located on top of the active site close to where FPP is bound. A76Y and A76Y/S77F OPPs mutants produce C20, indicating that the substituted larger residues interfere with the substrate chain elongation. Surprisingly, the A76Y/S77F mutant synthesizes a larger amount of C20 than the A76Y mutant. In the crystal structure of the A76Y/S77F mutant, F77 is pushed away by Y76, thereby crea...
TL;DR: High-resolution data clarified the FPP-binding mode compared with previously reported structures, and multiple sequence alignment indicated that the residues critical to the formation of the hydrophobic cavity and for coordinating the pyrophosphate group of FPP are present in the majority of MEDCP synthase enzymes, supporting the idea of a specialized biological function related to FPP binding in a subfamily of MED CP synthase homologs.
Abstract: Isopentenyl pyrophosphate (IPP) is a universal building block for the ubiquitous isoprenoids that are essential to all organisms. The enzymes of the non-mevalonate pathway for IPP synthesis, which is unique to many pathogenic bacteria, have recently been explored as targets for antibiotic development. Several crystal structures of 2C-methyl-d-erythritol-2,4-cyclophosphate (MECDP) synthase, the fifth of seven enzymes involved in the non-mevalonate pathway for synthesis of IPP, have been reported; however, the composition of metal ions in the active site and the presence of a hydrophobic cavity along the non-crystallographic threefold symmetry axis has varied between the reported structures. Here, the structure of MEDCP from Shewanella oneidensis MR1 (SO3437) was determined to 1.6 A resolution in the absence of substrate. The presence of a zinc ion in the active-site cleft, tetrahedrally coordinated by two histidine side chains, an aspartic acid side chain and an ambiguous fourth ligand, was confirmed by zinc anomalous diffraction. Based on analysis of anomalous diffraction data and typical metal-to-ligand bond lengths, it was concluded that an octahedral sodium ion was 3.94 A from the zinc ion. A hydrophobic cavity was observed along the threefold non-crystallographic symmetry axis, filled by a well defined non-protein electron density that could be modeled as farnesyl pyrophosphate (FPP), a downstream product of IPP, suggesting a possible feedback mechanism for enzyme regulation. The high-resolution data clarified the FPP-binding mode compared with previously reported structures. Multiple sequence alignment indicated that the residues critical to the formation of the hydrophobic cavity and for coordinating the pyrophosphate group of FPP are present in the majority of MEDCP synthase enzymes, supporting the idea of a specialized biological function related to FPP binding in a subfamily of MEDCP synthase homologs.
TL;DR: Results may suggest that pitavastatin attenuates SMC-mediated collagen gel contraction probably via an inhibition of geranylgeranylated Rho protein and a disruption of actin cytoskeletal reorganization.
Abstract: Constrictive arterial remodeling plays a major role in lumen narrowing following angioplasty. We investigated the effect of pitavastatin, a 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitor, on vascular smooth muscle cell (SMC)-populated collagen lattice contraction, an in vitro model of vascular contraction. Type I collagen gel contraction by SMCs, which are cultured in collagen gel, was used as a model of vascular remodeling. Pitavastatin pretreatment inhibited 10% serum- or platelet-derived growth factor-BB (PDGF)-induced SMC-mediated collagen lattice contraction in a concentration-dependent manner. The effect of pitavastatin was prevented by mevalonate or geranylgeranyl pyrophosphate, but not by squalene, a precursor of cholesterol, or farnesyl pyrophosphate. The serum- or PDGF-induced SMC-mediated collagen gel contraction was inhibited by GGTI-298, a geranylgeranyltransferase inhibitor, C3 exoenzyme, an inhibitor of Rho, or Y27634, a Rho kinase inhibitor, but not by FTI-277, a farnesyltransferase inhibitor. Serum or PDGF treatment increased the stress fiber organization in SMCs, which was blocked by the pitavastatin pretreatment. Pitavastatin had no effect on the serum- and PDGF-induced lamelliopodia extension of SMC. These results may suggest that pitavastatin attenuates SMC-mediated collagen gel contraction probably via an inhibition of geranylgeranylated Rho protein and a disruption of actin cytoskeletal reorganization.
TL;DR: Cerivastatin-induced blockade of ERK activation in ASM cells might result in growth inhibition including apoptosis, which might explain some aspects of the beneficial effects of cervastatin on coronary artery disease.
TL;DR: Data indicated that growth stimulation by TSH+Ins increased the activity of GGPP synthase with its increasing protein expression from G1/S transition, in which both cAMP-PKA and PI3-kinase pathways are involved in the proliferation of FRTL-5 cells.
Journal Article•
TL;DR: It could be inferred that cholesterol inhibitory activity of A. victorialis var.
Abstract: Cholesterol inhibitory activity was investigated to develop the functional food from edible forest resources such as Allium victorialis var. platyphyllum and other 12 species. Among tested samples by enzyme-linked immunosorbant assay (ELISA), leaf extracts of A. victorialis var. platyphyllum inhibited 73.9% of the activities of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) which is the highly regulated and major rate-limiting of the cholesterol biosynthesis pathway. Moreover, those extracts inhibited 76.7% of squalene synthase which catalyzes the head-to-head condensation of two farnesyl pyrophosphate molecules to form squalene in the biosynthesis of cholesterol. In order to find out the compounds which would play a key role in inhibitory activity of cholesterol, kaempferol and quercetin were isolated from the dichloromethane soluble fraction of extracts of A. victorialis var. platyphyllum Kampferol, quercetin and each soluble fraction was also subjected to the test of the Mrna expression of HMG-eoA reductase and squalene synthase by reverse transcriptase-polymerase chain reaction (RT-PeR) assay, respectively. By treating both enzymes with 10 of kaempferol and quercetin for 24 hours, respectively, the mRNA expression was not observed, suggesting that both compounds inhibited the biosynthesis of cholesterol at mRNA level. In this regard, it could be inferred that cholesterol inhibitory activity of A. victorialis var. platyphyllum was derived from kaempferol and quercetin. Both compounds have already been found in many plant extracts including hardwood and softwood, but it might be first known that they have cholesterol inhibitory activity.
TL;DR: The purified PTPase 1B enzyme exihibited dose-dependent phosphatase activity towards [gamma-(32)P]-ATP labeled mice beta-tubulin-encoded fusion protein and the dephosphorylation reaction with PTP enzyme 1B was enhanced with geranylgeranyl pyrophosphate, but not with farnesyl pyroph phosphate.
Abstract: Phosphotyrosyl protein phosphatase (PTPase) 1B was purified from human placenta. Immunoprecipitation analysis revealed that the isolated PTPase 1B appears as a complex with the receptor for protein kinase C (RACK1) and protein kinase C (PKC)delta. The abilities of PTPase 1B and PKCdelta to associate with RACK1 were reconfirmed by an in vitro reconstitution experiment. The E. coli expressed and biotinylated mice-RACK1-encoded fusion protein was capable of recruiting PTPase 1B and PKCdelta in the antibiotin immunoprecipitate as a complex of PTPase 1B/RACK1/PKCdelta. Thus PTPase 1B enzyme preparation was subjected to further purification by selective binding of PTPase 1B onto PEP(Taxol) affinity column in the absence of ATP. The purified PTPase 1B enzyme exihibited dose-dependent phosphatase activity towards [gamma-(32)P]-ATP labeled mice beta-tubulin-encoded fusion protein. The dephosphorylation reaction with PTPase 1B was enhanced with geranylgeranyl pyrophosphate, but not with farnesyl pyrophosphate. Interestingly, additional incubation of the purified PTPase 1B enzyme preparation with RACK1, geranylgeranyl pyrophosphate failed to modulate the dephosphorylation activity of PTPase 1B. In contrast, the enhancement effect of farnesyl pyrophosphate on the kinase activity of PKCdelta was sustained in the presence of RACK1. That is, farnesyl pyrophosphate may function as a signal to induce the kinase activity of PKCdelta in PTPase 1B/RACK1/PKCdelta complex but geranylgeranyl pyrophosphate may not for PTPase 1B. J. Exp. Zool. 301A:307-316, 2004.
Patent•
26 Mar 2004TL;DR: A carotenogenic biosynthetic gene cluster has been isolated from Panteoa stewartii strain DC413, wherein the genetic organization of the cluster is crtE-idi-crtX-CrtY-crTI-crtpB-CRtZ as mentioned in this paper, where the genes contained within this cluster encode geranylgeranyl pyrophosphate (GGPP) synthetase (CrtE), isopentenyl pyrophophosphate isomerase (Idi), zeaxanthin glucosyl transferase(Cr
Abstract: A carotenogenic biosynthetic gene cluster has been isolated from Panteoa stewartii strain DC413, wherein the genetic organization of the cluster is crtE-idi-crtX-crtY-crtI-crtB-crtZ. The genes contained within this cluster encode geranylgeranyl pyrophosphate (GGPP) synthetase (CrtE), isopentenyl pyrophosphate isomerase (Idi), zeaxanthin glucosyl transferase (CrtX), lycopene cyclase (CrtY), phytoene desaturase (CrtI), phytoene synthase (CrtB), and β-carotene hydroxylase (CrtZ). The gene cluster, genes and their products are useful for the conversion of farnesyl pyrophosphate to carotenoids. Vectors containing those DNA segments, host cells containing the vectors and methods for producing those enzymes by recombinant DNA technology in transformed host organisms are disclosed.
Patent•
06 Oct 2004
TL;DR: A nucleotide sequence and protein of hop farnesyl pyrophosphate synthase was described in this article, and the protein was shown to be a hop-farnesyl protein.
Abstract: A nucleotide sequence and protein of the hop farnesyl pyrophosphate synthase is described herein.
01 Jan 2004
TL;DR: Subsequent pre-clinical research revealed that other intracellular proteins than Ras are involved in the antiproliferative effects of farnesyl protein transferase inhibition; these insights are corroborated by clinical research indicating that antitumour activity is mainly seen in tumour types which do not harbor K-ras mutations.
Abstract: The development of inhibitors of the farnesyl protein transferase enzyme and their potential role as targeted anti-cancer therapies has historically been driven by the recognition of the importance of farnesylation in the activity of normal and mutated Ras proteins. For the Ras proteins to transduce the extracellular signals provided by growth factors and cytokines, they must be anchored to the inner surface of the plasma membrane. This association is facilitated by a series of posttranslational chemical modifications, the first one of which is a farnesylation reaction catalyzed by the farnesyl protein transferase enzyme.45 It was hypothesized that inhibition of this reaction would prevent the association of Ras proteins with the cell membrane, therefore block the constitutive activity of mutated Ras or the growth factor driven activity of wild type Ras, and as such inhibit the growth of tumours, such as pancreatic cancer, in which Ras is thought to play a major role in oncogenesis and tumour growth.6 Subsequent pre-clinical research has revealed that other intracellular proteins than Ras are involved in the antiproliferative effects of farnesyl protein transferase inhibition; these insights are corroborated by clinical research indicating that antitumour activity is mainly seen in tumour types which do not harbor K-ras mutations.
TL;DR: PA treatment inhibited growth of MCF-7, NIH-3T3, Detroit 551, UT-2, NCTC-929, COS-1 and PC-3 cell lines and negative TUNEL assay results and failure to block cell loss with z-VAD-fmk suggest cell death is responsible for the lower rates of cell and protein accumulation.
Abstract: Phenylacetate (PA) is a reversible inhibitor of tumor cell growth and an inhibitor of mevalonate pyrophosphate decarboxylase (MPD). We hypothesized that MPD inhibition should lower rates of protein accumulation and accretion of cell number in all cell lines regardless of tumorigenic status or origin of the cell lines. PA treatment inhibited growth of MCF-7, NIH-3T3, Detroit 551, UT-2, NCTC-929, COS-1 and PC-3 cell lines. NCTC-929 cells lack cadherins and Cos-1 cells are deficient in PPARalpha and PPARgamma, proteins suggested to be central to the action of PA. Oxidative metabolism was not impeded by PA treatment. One-dimensional and two-dimensional FACS analysis of BrdU incorporation failed to demonstrate a redistribution of nuclei in the cell cycle or that the rate of cells entering S phase had changed. Time-lapse photo-microscopy studies reveal a process that left condensed nuclei with little or no cytoplasm. However, negative TUNEL assay results and failure to block cell loss with z-VAD-fmk suggest this type of cell death is not typical apoptosis, but cell death is responsible for the lower rates of cell and protein accumulation. Supplementation studies with mevalonate pathway intermediates during inhibition of the mevalonate pathway of cholesterol biosynthesis by lovastatin confirmed MPD as a site of PA inhibition of growth, but in the presence of lovastatin with or without farnesyl pyrophosphate plus geranylgeranyl pyrophosphate, additive inhibition by PA revealed additional site(s). The existence of site(s) in addition to MPD suggests effective PA-based agents might be developed that would not inhibit MPD.