scholarly journals Epigenetic Modifiers Revamp Secondary Metabolite Production in Endophytic Nigrospora sphaerica

2021 ◽  
Vol 12 ◽  
Author(s):  
Kolathuru Puttamadaiah Ramesha ◽  
Nagabhushana Chandra Mohana ◽  
Siddaiah Chandra Nayaka ◽  
Sreedharamurthy Satish
Keyword(s):  
Secondary Metabolite ◽  
High Performance ◽  
Dna Methyltransferase ◽  
Epigenetic Modification ◽  
Hdac Inhibitors ◽  
Biological Significance ◽  
Gene Clusters ◽  
Gas Chromatography Mass Spectrometry ◽  
Epigenetic Modifiers ◽  
Biological Potential

During plant interaction, endophytes provide benefits to the host plant. Endophytes also contribute a variety of structural attributes with biological potential. Nigrospora sphaerica, which produces phomalactone from Adiantum philippense L., was subjected to epigenetic modification. High-performance liquid chromatography (HPLC) and Gas chromatography-mass spectrometry (GCMS) analysis were used to determine secondary metabolite profiling. Epigenetic modifiers like DNA Methyltransferase (DNMT) and Histone deacetylase (HDAC) inhibitors increased the expression of biosynthetic pathways. The activation of new metabolites was observed as a result of the activation of cryptic biosynthetic gene clusters, as well as the silencing of phomalactone in some treatments. When compared to DNMT treatments, HDAC treatments showed a significant increase in cryptic metabolite induction. The induction of cryptic metabolites with biological significance by HDAC treatment is supported by our findings.

scholarly journals Histone Deacetylase Activity Regulates Chemical Diversity in Aspergillus

2007 ◽  
Vol 6 (9) ◽  
pp. 1656-1664 ◽  
Author(s):  
E. Keats Shwab ◽  
Jin Woo Bok ◽  
Martin Tribus ◽  
Johannes Galehr ◽  
Stefan Graessle ◽  
...  
Keyword(s):  
Small Molecules ◽  
Aspergillus Nidulans ◽  
Histone Deacetylase ◽  
Secondary Metabolite ◽  
Filamentous Fungi ◽  
Small Molecule ◽  
Transcriptional Activation ◽  
Hdac Inhibitors ◽  
Gene Clusters ◽  
Chemical Diversity

ABSTRACT Bioactive small molecules are critical in Aspergillus species during their development and interaction with other organisms. Genes dedicated to their production are encoded in clusters that can be located throughout the genome. We show that deletion of hdaA, encoding an Aspergillus nidulans histone deacetylase (HDAC), causes transcriptional activation of two telomere-proximal gene clusters—and subsequent increased levels of the corresponding molecules (toxin and antibiotic)—but not of a telomere-distal cluster. Introduction of two additional HDAC mutant alleles in a ΔhdaA background had minimal effects on expression of the two HdaA-regulated clusters. Treatment of other fungal genera with HDAC inhibitors resulted in overproduction of several metabolites, suggesting a conserved mechanism of HDAC repression of some secondary-metabolite gene clusters. Chromatin regulation of small-molecule gene clusters may enable filamentous fungi to successfully exploit environmental resources by modifying chemical diversity.

Genome sequence of Novosphingobium malaysiense strain MUSC 273T, novel alpha-proteobacterium isolated from intertidal soil

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Hooi-Leng Ser ◽  
Wai-Fong Yin ◽  
Kok-Gan Chan ◽  
Nurul-Syakima Ab Mutalib ◽  
Learn-Han Lee
Keyword(s):  
Secondary Metabolites ◽  
Secondary Metabolite ◽  
Genome Sequence ◽  
Catalase Activity ◽  
Gene Clusters ◽  
Rrna Genes ◽  
Gram Negative ◽  
Genomic Features

Novosphingobium malaysiense strain MUSC 273T is a recently identified Gram-negative, aerobic alpha-proteobacterium. The strain was isolated from intertidal soil with strong catalase activity. The genome sequence comprises 5,027,021 bp, with 50 tRNA and 3 rRNA genes. Further analysis identified presence of secondary metabolite gene clusters within genome of MUSC 273T. Knowledge of the genomic features of the strain may allow further biotechnological exploitation, particularly for production of secondary metabolites as well as production of industrially important enzymes

Application of a fractionation technique for better understanding of the removal of natural organic matter by alum coagulation

2002 ◽  
Vol 2 (5-6) ◽  
pp. 427-433 ◽  
Author(s):  
J. van Leeuwen ◽  
C. Chow ◽  
R. Fabris ◽  
N. Withers ◽  
D. Page ◽  
...  
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
High Performance ◽  
Relative Proportion ◽  
Water Source ◽  
Size Exclusion ◽  
Gas Chromatography Mass Spectrometry ◽  
Pyrolysis Gas ◽  
Alum Treatment ◽  
Hydrophobic Acids

To gain an improved understanding of the types of organic compounds that are recalcitrant to water treatment, natural organic matter (NOM) isolates from two drinking water sources (Mt. Zero and Moorabool reservoirs, Victoria, Australia) were separated into fractions of distinct chemical behaviour using resins. Four fractions were obtained from each water source and were organics absorbed to: (1) XAD-8 (very hydrophobic acids, VHA); (2) DAX-4 (slightly hydrophobic acids, SHA); (3) bound to an anion exchange resin (charged organics, CHAR); and (4) not absorbed or bound to resins (neutrals, NEUT). These fractions were then tested to determine the capacity of alum to remove them from water and to correlate this with the character of each isolate. The fractions were characterised by the application of high performance size exclusion chromatography (HPSEC), bacterial regrowth potential (BRP), trihalomethane formation potential (THMFP), pyrolysis gas-chromatography mass spectrometry (Py-GC-MS) and thermochemolysis. The highest removals of dissolved organic carbon (DOC) by alum treatment were in waters spiked with the CHAR fractions while the NEUT fractions were the most recalcitrant. The number average molecular weights (Mn) of DOC of the CHAR fractions before treatment were the highest, whilst those of the NEUT fractions were the lowest. After alum treatment, the Mn of the NEUT fractions were only slightly reduced. Results from Py-GC-MS and thermochemolysis indicate that the NEUT fractions had the highest relative proportion of saccharide derived organic material. Nonetheless, the BRP of waters spiked with the NEUT fractions differed markedly, indicating that organics recalcitrant to alum treatment can vary substantially in their chemical composition and capacity to support microbial growth.

scholarly journals Investigation of the Antifungal and Anti-Aflatoxigenic Potential of Plant-Based Essential Oils against Aspergillus flavus in Peanuts

2020 ◽  
Vol 6 (4) ◽  
pp. 383
Author(s):  
Premila Narayana Achar ◽  
Pham Quyen ◽  
Emmanuel C. Adukwu ◽  
Abhishek Sharma ◽  
Huggins Zephaniah Msimanga ◽  
...  
Keyword(s):  
Essential Oils ◽  
Aspergillus Flavus ◽  
High Performance ◽  
Opportunistic Infections ◽  
Aflatoxin Production ◽  
The United States ◽  
Microscopy Study ◽  
Aspergillus Species ◽  
Gas Chromatography Mass Spectrometry ◽  
Ammonia Vapor

Aspergillus species are known to cause damage to food crops and are associated with opportunistic infections in humans. In the United States, significant losses have been reported in peanut production due to contamination caused by the Aspergillus species. This study evaluated the antifungal effect and anti-aflatoxin activity of selected plant-based essential oils (EOs) against Aspergillus flavus in contaminated peanuts, Tifguard, runner type variety. All fifteen essential oils, tested by the poisoned food technique, inhibited the growth of A. flavus at concentrations ranging between 125 and 4000 ppm. The most effective oils with total clearance of the A. flavus on agar were clove (500 ppm), thyme (1000 ppm), lemongrass, and cinnamon (2000 ppm) EOs. The gas chromatography-mass spectrometry (GC-MS) analysis of clove EO revealed eugenol (83.25%) as a major bioactive constituent. An electron microscopy study revealed that clove EO at 500 ppm caused noticeable morphological and ultrastructural alterations of the somatic and reproductive structures. Using both the ammonia vapor (AV) and coconut milk agar (CMA) methods, we not only detected the presence of an aflatoxigenic form of A. flavus in our contaminated peanuts, but we also observed that aflatoxin production was inhibited by clove EO at concentrations between 500 and 2000 ppm. In addition, we established a correlation between the concentration of clove EO and AFB1 production by reverse-phase high-performance liquid chromatography (HPLC). We demonstrate in our study that clove oil could be a promising natural fungicide for an effective bio-control, non-toxic bio-preservative, and an eco-friendly alternative to synthetic additives against A. flavus in Georgia peanuts.

scholarly journals Histochemical and Phytochemical Analysis of Lamium album subsp. album L. Corolla: Essential Oil, Triterpenes, and Iridoids

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4166
Author(s):  
Agata Konarska ◽  
Elżbieta Weryszko-Chmielewska ◽  
Anna Matysik-Woźniak ◽  
Aneta Sulborska ◽  
Beata Polak ◽  
...  
Keyword(s):  
Essential Oil ◽  
High Performance ◽  
Glandular Trichomes ◽  
Gas Chromatography Mass Spectrometry ◽  
Phytochemical Analysis ◽  
Lipophilic Compounds ◽  
Histochemical Tests ◽  
Microscopy Techniques ◽  
Trichome Types ◽  
First Time

The aim of this study was to conduct a histochemical analysis to localize lipids, terpenes, essential oil, and iridoids in the trichomes of the L. album subsp. album corolla. Morphometric examinations of individual trichome types were performed. Light and scanning electron microscopy techniques were used to show the micromorphology and localization of lipophilic compounds and iridoids in secretory trichomes with the use of histochemical tests. Additionally, the content of essential oil and its components were determined using gas chromatography-mass spectrometry (GC-MS). Qualitative analyses of triterpenes carried out using high-performance thin-layer chromatography (HPTLC) coupled with densitometric detection, and the iridoid content expressed as aucubin was examined with spectrophotometric techniques. We showed the presence of iridoids and different lipophilic compounds in papillae and glandular and non-glandular trichomes. On average, the flowers of L. album subsp. album yielded 0.04 mL/kg of essential oil, which was dominated by aldehydes, sesquiterpenes, and alkanes. The extract of the L. album subsp. album corolla contained 1.5 × 10−3 ± 4.3 × 10−4 mg/mL of iridoid aucubin and three triterpenes: oleanolic acid, β-amyrin, and β-amyrin acetate. Aucubin and β-amyrin acetate were detected for the first time. We suggest the use of L. album subsp. album flowers as supplements in human nutrition.

scholarly journals Hydrothermal Pretreatment of Wheat Straw: Effects of Temperature and Acidity on Byproduct Formation and Inhibition of Enzymatic Hydrolysis and Ethanolic Fermentation

Agronomy ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 487
Author(s):  
Dimitrios Ilanidis ◽  
Stefan Stagge ◽  
Leif J. Jönsson ◽  
Carlos Martín
Keyword(s):  
Mass Spectrometry ◽  
Sulfuric Acid ◽  
Wheat Straw ◽  
High Performance ◽  
Enzymatic Saccharification ◽  
Hydrothermal Pretreatment ◽  
Gas Chromatography Mass Spectrometry ◽  
Enzymatic Digestibility ◽  
Acid Catalyzed ◽  
Pretreatment Conditions

Biochemical conversion of wheat straw was investigated using hydrothermal pretreatment, enzymatic saccharification, and microbial fermentation. Pretreatment conditions that were compared included autocatalyzed hydrothermal pretreatment at 160, 175, 190, and 205 °C and sulfuric-acid-catalyzed hydrothermal pretreatment at 160 and 190 °C. The effects of using different pretreatment conditions were investigated with regard to (i) chemical composition and enzymatic digestibility of pretreated solids, (ii) carbohydrate composition of pretreatment liquids, (iii) inhibitory byproducts in pretreatment liquids, (iv) furfural in condensates, and (v) fermentability using yeast. The methods used included two-step analytical acid hydrolysis combined with high-performance anion-exchange chromatography (HPAEC), HPLC, ultra-high performance liquid chromatography-electrospray ionization-triple quadrupole-mass spectrometry (UHPLC-ESI-QqQ-MS), and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Lignin recoveries in the range of 108–119% for autocatalyzed hydrothermal pretreatment at 205 °C and sulfuric-acid-catalyzed hydrothermal pretreatment were attributed to pseudolignin formation. Xylose concentration in the pretreatment liquid increased with temperature up to 190 °C and then decreased. Enzymatic digestibility was correlated with the removal of hemicelluloses, which was almost quantitative for the autocatalyzed hydrothermal pretreatment at 205 °C. Except for the pretreatment liquid from the autocatalyzed hydrothermal pretreatment at 205 °C, the inhibitory effects on Saccharomyces cerevisiae yeast were low. The highest combined yield of glucose and xylose was achieved for autocatalyzed hydrothermal pretreatment at 190 °C and the subsequent enzymatic saccharification that resulted in approximately 480 kg/ton (dry weight) raw wheat straw.

scholarly journals 8a, a New Acridine Antiproliferative and Pro-Apoptotic Agent Targeting HDAC1/DNMT1

2021 ◽  
Vol 22 (11) ◽  
pp. 5516
Author(s):  
Qiting Zhang ◽  
Ziyan Wang ◽  
Xinyuan Chen ◽  
Haoxiang Qiu ◽  
Yifan Gu ◽  
...  
Keyword(s):  
Histone Deacetylase ◽  
Dna Methyltransferase ◽  
Hdac Inhibitors ◽  
Mitochondrial Pathway ◽  
Epigenetic Therapy ◽  
Protein Interaction Data ◽  
Dependent Manner ◽  
Histone Deacetylase 1 ◽  
Histiocytic Lymphoma ◽  
Dose Dependent

Epigenetic therapy using histone deacetylase (HDAC) inhibitors has become an attractive project in new drug development. However, DNA methylation and histone acetylation are important epigenetic ways to regulate the occurrence and development of leukemia. Given previous studies, N-(2-aminophenyl)benzamide acridine (8a), as a histone deacetylase 1 (HDAC1) inhibitor, induces apoptosis and shows significant anti-proliferative activity against histiocytic lymphoma U937 cells. HDAC1 plays a role in the nucleus, which we confirmed by finding that 8a entered the nucleus. Subsequently, we verified that 8a mainly passes through the endogenous (mitochondrial) pathway to induce cell apoptosis. From the protein interaction data, we found that 8a also affected the expression of DNA methyltransferase 1 (DNMT1). Therefore, an experiment was performed to assess the binding of 8a to DNMT1 at the molecular and cellular levels. We found that the binding strength of 8a to DNMT1 enhanced in a dose-dependent manner. Additionally, 8a inhibits the expression of DNMT1 mRNA and its protein. These findings suggested that the anti-proliferative and pro-apoptotic activities of 8a against leukemia cells were achieved by targeting HDAC1 and DNMT1.

Identification of the kinanthraquinone biosynthetic gene cluster by expression of an atypical response regulator

2021 ◽  
Vol 85 (3) ◽  
pp. 714-721
Author(s):  
Risa Takao ◽  
Katsuyuki Sakai ◽  
Hiroyuki Koshino ◽  
Hiroyuki Osada ◽  
Shunji Takahashi
Keyword(s):  
Heterologous Expression ◽  
Gene Cluster ◽  
Secondary Metabolite ◽  
Response Regulator ◽  
Bac Library ◽  
Gene Clusters ◽  
Biosynthetic Gene Cluster ◽  
Gene Organization ◽  
Biosynthetic Gene ◽  
Streptomyces Sp

ABSTRACT Recent advances in genome sequencing have revealed a variety of secondary metabolite biosynthetic gene clusters in actinomycetes. Understanding the biosynthetic mechanism controlling secondary metabolite production is important for utilizing these gene clusters. In this study, we focused on the kinanthraquinone biosynthetic gene cluster, which has not been identified yet in Streptomyces sp. SN-593. Based on chemical structure, 5 type II polyketide synthase gene clusters were listed from the genome sequence of Streptomyces sp. SN-593. Among them, a candidate gene cluster was selected by comparing the gene organization with grincamycin, which is synthesized through an intermediate similar to kinanthraquinone. We initially utilized a BAC library for subcloning the kiq gene cluster, performed heterologous expression in Streptomyces lividans TK23, and identified the production of kinanthraquinone and kinanthraquinone B. We also found that heterologous expression of kiqA, which belongs to the DNA-binding response regulator OmpR family, dramatically enhanced the production of kinanthraquinones.

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