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Showing papers on "Lanosterol published in 2014"


Journal ArticleDOI
TL;DR: Improve the production of individual GAs by engineering the biosynthetic pathway of GAs in G. lucidum through the overexpression of squalene synthase (SQS) gene, suggesting that increased GA biosynthesis may result from a higher expression of those genes.

53 citations


Journal ArticleDOI
24 Oct 2014-PLOS ONE
TL;DR: A CAS1-specific functional sterol pathway in engineered yeast, and a strict dependence on CAS1 of tobacco sterol biosynthesis are shown.
Abstract: The plant sterol pathway exhibits a major biosynthetic difference as compared with that of metazoans. The committed sterol precursor is the pentacyclic cycloartenol (9β,19-cyclolanost-24-en-3β-ol) and not lanosterol (lanosta-8,24-dien-3β-ol), as it was shown in the late sixties. However, plant genome mining over the last years revealed the general presence of lanosterol synthases encoding sequences (LAS1) in the oxidosqualene cyclase repertoire, in addition to cycloartenol synthases (CAS1) and to non-steroidal triterpene synthases that contribute to the metabolic diversity of C30H50O compounds on earth. Furthermore, plant LAS1 proteins have been unambiguously identified by peptidic signatures and by their capacity to complement the yeast lanosterol synthase deficiency. A dual pathway for the synthesis of sterols through lanosterol and cycloartenol was reported in the model Arabidopsis thaliana, though the contribution of a lanosterol pathway to the production of 24-alkyl-Δ5-sterols was quite marginal (Ohyama et al. (2009) PNAS 106, 725). To investigate further the physiological relevance of CAS1 and LAS1 genes in plants, we have silenced their expression in Nicotiana benthamiana. We used virus induced gene silencing (VIGS) based on gene specific sequences from a Nicotiana tabacum CAS1 or derived from the solgenomics initiative (http://solgenomics.net/) to challenge the respective roles of CAS1 and LAS1. In this report, we show a CAS1-specific functional sterol pathway in engineered yeast, and a strict dependence on CAS1 of tobacco sterol biosynthesis.

51 citations


Journal ArticleDOI
TL;DR: The results indicate that acetic acid alters the expression of genes related to acetic Acid assimilation and increases GA biosynthesis and the metabolic levels of lanosterol, squalene and GA-a, thereby resulting in GA accumulation.
Abstract: Acetic acid at 5–8 mM increased ganoderic acid (GA) accumulation in Ganoderma lucidum. After optimization by the response surface methodology, the GA content reached 5.5/100 mg dry weight, an increase of 105 % compared with the control. The intermediate metabolites of GA biosynthesis, lanosterol and squalene also increased to 47 and 15.8 μg/g dry weight, respectively, in response to acetic acid. Acetic acid significantly induced transcription levels of sqs, lano, hmgs and cyp51 in the GA biosynthesis pathway. An acetic acid-unregulated acetyl coenzyme A synthase (acs) gene was selected from ten candidate homologous acs genes. The results indicate that acetic acid alters the expression of genes related to acetic acid assimilation and increases GA biosynthesis and the metabolic levels of lanosterol, squalene and GA-a, thereby resulting in GA accumulation.

39 citations


Journal ArticleDOI
TL;DR: It is reported that SM is stabilized by unsaturated fatty acids, and the mechanism of oleate-mediated stabilization appeared to occur through reduced ubiquitination by the E3 ubiquitin ligase MARCH6.
Abstract: SM (squalene mono-oxygenase) catalyses the first oxygenation step in cholesterol synthesis, immediately before the formation of the steroid backbone at lanosterol. SM is an important control point in the pathway, and is regulated at the post-translational level by accelerated cholesterol-dependent ubiquitination and proteasomal degradation, which is associated with the accumulation of squalene. Using model cell systems, we report that SM is stabilized by unsaturated fatty acids. Treatment with unsaturated fatty acids such as oleate, but not saturated fatty acids, increased protein levels of SM or SM-N100–GFP (the first 100 amino acids of SM fused to GFP) at the post-translational level and partially overcame cholesterol-dependent degradation, as well as reversing cholesterol-dependent squalene accumulation. Maximum stabilization required activation of fatty acids, but not triacylglycerol or phosphatidylcholine synthesis. The mechanism of oleate-mediated stabilization appeared to occur through reduced ubiquitination by the E3 ubiquitin ligase MARCH6. Stabilization of a cholesterol biosynthetic enzyme by unsaturated fatty acids may help maintain a constant cholesterol/phospholipid ratio.

35 citations


Journal ArticleDOI
Nanhao Chen1, Jingwei Zhou1, Jiabo Li2, Jun Xu1, Ruibo Wu1 
TL;DR: State-of-the-art ab initio QM/MM MD simulations are employed to investigate the detailed cyclization mechanism of C-ring and D-ring formation and reveal that the C and D rings are formed near-synchronously from a stable "6-6-5" ring intermediate.
Abstract: Human oxidosqualene cyclase (OSC) is one key enzyme in the biosynthesis of cholesterol. It can catalyze the linear-chain 2,3-oxidosqualene to form lanosterol, the tetracyclic (6-6-6-5 members for A-B-C-D rings) cholesterol precursor. It also has been treated as a novel antihyperlipidemia target. In addition, the structural diversity of cyclic terpenes in plants originates from the cyclization of 2,3-oxidosqualene. The enzyme catalytic mechanism is considered to be one of the most complicated ones in nature, and there are a lot of controversies about the mechanism in the past half a century. Herein, state-of-the-art ab initio QM/MM MD simulations are employed to investigate the detailed cyclization mechanism of C-ring and D-ring formation. Our study reveals that the C and D rings are formed near-synchronously from a stable "6-6-5" ring intermediate. Interestingly, the transition state of this concerted reaction presents a "6-6-6" structure motif, while this unstable "6-6-6" structure in our simulations is thought to be a stable intermediate state in most previous hypothetical mechanisms. Furthermore, as the tailed side chain of 2,3-oxidosqualene shows a β conformation while it is α conformation in lanosterol, finally, it is observed that the rotatable "tail" chain prefers to transfer β conformation to α conformation at the "6-6-5" intermediate state.

28 citations


Journal ArticleDOI
TL;DR: Biochemical and computational analyses are consistent with lanosterol being a substrate for early deuterostome CYP51s, and the results expand the phylogenetic view of animal CYP 51, with evolutionary, environmental and therapeutic implications.

26 citations


Journal ArticleDOI
TL;DR: It is shown that these compounds lower ergosterol levels in the fungal cells and probably act by targeting lanosterol 14α-demethylase, a key enzyme in the sterol biosynthetic pathway of C. albicans.

22 citations


Journal ArticleDOI
TL;DR: Trans-2-(1-Pentyl)-3-imidazolylchroman-4-one (4d) showed the most potent activity against yeasts comparable to fluconazole, and docking study with 14α-demethylase demonstrated that the di-axial form of compound 4d can be considered as active conformation.
Abstract: Previously, 2-alkylchromans have been introduced as non-azole inhibitors of 14α-demethylase. Accordingly, we incorporated imidazole ring on the 3-position of 2-alkylchromanones to design new inhibitors of 14α-demethylase and potential antifungal agents. Thus, a series of 2-alkyl-3-imidazolylchromanones were synthesized starting from 2-hydroxyphenacyl bromide. The trans-configuration of compounds was confirmed by NMR-spectroscopy. The antifungal activity of title compounds were evaluated against different fungi in comparison with fluconazole and miconazole. trans-2-(1-Pentyl)-3-imidazolylchroman-4-one (4d) showed the most potent activity against yeasts comparable to fluconazole. The experimental data based on (1)H NMR spectroscopy revealed that 2-alkyl side chain and 3-imidazolyl moiety in compound 4d exist predominantly in the di-equatorial conformation. While docking study with 14α-demethylase demonstrated that the di-axial form of compound 4d can be considered as active conformation.

18 citations


Journal ArticleDOI
TL;DR: A role for FoxO4 in the regulation of CYP51 expression is demonstrated in adipose tissue of ob/ob mice and mouse fetal cortical neurons exposed to hypoxia.

14 citations


Journal ArticleDOI
TL;DR: A molecular modeling study of the binding interactions between compounds 6, 7d, 8g and the active site of MtCYP51 was conducted based on the computational docking results.
Abstract: The development of antifungal drugs that inhibit lanosterol 14-α-demethylase (CYP51) via non-covalent ligand interactions is a strategy that is gaining importance. A series of novel tetraindol-4-one derivatives with 1- and 2-(2,4-substituted phenyl) side chains were designed and synthesized based on the structure of CYP51 and fluconazole. The antifungal activities of these derivatives against eight human pathogenic filamentous fungi and yeast strains were evaluated in vitro by measuring the minimal inhibitory concentrations. Nearly all tested compounds 8a-g displayed activity against Candida tropicalis, Candida guilliermondii and Candida parapsilosis with a minimum inhibitory concentration (MIC) value until 8 µg mL(-1), on the other hand compounds 7a-g showed activity against Aspergillus fumigatus with a MIC value of 31.25 µg mL(-1). A molecular modeling study of the binding interactions between compounds 6, 7d, 8g and the active site of MtCYP51 was conducted based on the computational docking results.

13 citations


Journal Article
01 Jan 2014-Scopus
TL;DR: Comparison of the protein sequences and phylogenetic analysis revealed that the M. perniciosa enzyme was most closely related to that of Coprinopsis cinerea, the causal agent of witches' broom disease of cocoa.
Abstract: The phytopathogenic fungus Moniliophthora perniciosa (Stahel) Aime & Philips-Mora, causal agent of witches’ broom disease of cocoa, causes countless damage to cocoa production in Brazil. Molecular studies have attempted to identify genes that play important roles in fungal survival and virulence. In this study, sequences deposited in the M. perniciosa Genome Sequencing Project database were analyzed to identify potential biological targets. For the first time, the ergosterol biosynthetic pathway in M. perniciosa was studied and the lanosterol 14-demethylase gene (ERG11) that encodes the main enzyme of this pathway and is a target for fungicides was cloned, characterized molecularly and its phylogeny analyzed. ERG11 genomic DNA and cDNA were characterized and sequence analysis of the ERG11 protein identified highly conserved domains typical of this enzyme, such as SRS1, SRS4, EXXR and the heme-binding region (HBR). Comparison of the protein sequences and phylogenetic analysis revealed that the M. perniciosa enzyme was most closely related to that of Coprinopsis cinerea.

Journal ArticleDOI
TL;DR: Screening of potential ligands of human CYP51 (CYP51A1) among natural low-weight compounds containing steroid-like moiety has been performed by means of integration of surface plasmon resonance and spectral titration methods, and four compounds exhibited high affinity to the active site of CYP 51A1.
Abstract: Inhibition of cholesterol biosynthesis at post-squalene steps provide the alternative to classic statin therapy. Sterol-14α-demethylase (CYP51) is one of potential targets for such inhibition. In this study screening of potential ligands of human CYP51 (CYP51A1) among natural low-weight compounds containing steroid-like moiety has been performed by means of integration of surface plasmon resonance and spectral titration methods. Four compounds (betulafolientriol, holothurin A, theasaponin, capsicosine) exhibited high affinity to the active site of CYP51A1. These data extend the known range of compounds, which may be used as specific inhibitors of CYP51.

Journal ArticleDOI
TL;DR: The screening of the ability to interact with human CYP51 (CYP51A1) for the nature low-weight compounds with steroid-like scaffold were performed by integration of the surface plasmon resonance biosensor and spectral titration methods.
Abstract: The cholesterol biosynthesis regulation is the important part of the hypercholesterolemia diseases therapy. The inhibition of the post-squalene cholesterol biosynthesis steps provide the alternative to classic statin therapy. Sterol-14a-demethylase (CYP51) is one of the hypothetical targets for it. In this work the screening of the ability to interact with human CYP51 (CYP51A1) for the nature low-weight compounds with steroid-like scaffold were performed by integration of the surface plasmon resonance biosensor and spectral titration methods. The results of the selection were 4 compounds (betulafolientriol, holothurin A, teasaponin, capsicoside A) witch had high affinity to the CYP51A1 active site. These data extend the range of compounds which may be used as specific inhibitors of CYP51 and give the permission to suggest the dynamic of the enzyme.

Journal Article
TL;DR: Results showed that EHEF can decrease the membrane CYP51 enzyme activity, and it also can accumulate the fungal lanosterol in a dose-dependent manner, and the gene expression of MEP and SUB can decrease.
Abstract: This study is to investigate the effect of Euphorbia humifusa effective fraction (EHEF) on the CYP51 enzyme activity, the lanosterol content and the MEP, SUB gene expression of Trichophyton rubrum Trichophyton rubrum was treated by EHEF for 7 days at 26 degrees C The activity of CYP51 enzyme of Trichophyton rubrum in the cell membrane was determined by using ELISA kit, and the lanosterol content was investigated by using high performance liquid chromatography (HPLC), and the MEP, SUB gene expression of Trichophyton rubrum was detected with the reverse transcription polymerase chain reaction (RT-PCR) method Results showed that EHEF can decrease the membrane CYP51 enzyme activity, and it also can accumulate the fungal lanosterol in a dose-dependent manner, and it also can decrease the gene expression of MEP and SUB The antifungal mechanism of EHEF may be related to the inhibition on CYP51 enzyme activity, and to the effects on fungal cell membrane ergosterol biosynthesis It may also play an antifungal effect by inhibiting the MEP, SUB gene expression of fungal proteases