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  1. Article ; Online: Biosynthesis of polyprenylated xanthones in Hypericum perforatum roots involves 4-prenyltransferase.

    Sayed, Hesham M B / Nassar, Sara / Kaufholdt, David / Beerhues, Ludger / Liu, Benye / El-Awaad, Islam

    Plant physiology

    2023  Volume 192, Issue 4, Page(s) 2971–2988

    Abstract: Polyprenylated xanthones are natural products with a multitude of biological and pharmacological activities. However, their biosynthetic pathway is not completely understood. In this study, metabolic profiling revealed the presence of 4-prenylated 1,3,5, ... ...

    Abstract Polyprenylated xanthones are natural products with a multitude of biological and pharmacological activities. However, their biosynthetic pathway is not completely understood. In this study, metabolic profiling revealed the presence of 4-prenylated 1,3,5,6-tetrahydroxyxanthone derivatives in St. John's wort (Hypericum perforatum) root extracts. Transcriptomic data mining led to the detection of 5 variants of xanthone 4-prenyltransferase (HpPT4px) comprising 4 long variants (HpPT4px-v1 to HpPT4px-v4) and 1 short variant (HpPT4px-sh). The full-length sequences of all 5 variants were cloned and heterologously expressed in yeast (Saccharomyces cerevisiae). Microsomes containing HpPT4px-v2, HpPT4px-v4, and HpPT4px-sh catalyzed the addition of a prenyl group at the C-4 position of 1,3,5,6-tetrahydroxyxanthone; 1,3,5-trihydroxyxanthone; and 1,3,7-trihydroxyxanthone, whereas microsomes harboring HpPT4px-v1 and HpPT4px-v3 additionally accepted 1,3,6,7-tetrahydroxyxanthone. HpPT4px-v1 produced in Nicotiana benthamiana displayed the same activity as in yeast, while HpPT4px-sh was inactive. The kinetic parameters of HpPT4px-v1 and HpPT4px-sh chosen as representative variants indicated 1,3,5,6-tetrahydroxyxanthone as the preferred acceptor substrate, rationalizing that HpPT4px catalyzes the first prenylation step in the biosynthesis of polyprenylated xanthones in H. perforatum. Dimethylallyl pyrophosphate was the exclusive prenyl donor. Expression of the HpPT4px transcripts was highest in roots and leaves, raising the question of product translocation. C-terminal yellow fluorescent protein fusion of HpPT4px-v1 localized to the envelope of chloroplasts in N. benthamiana leaves, whereas short, truncated, and masked signal peptides led to the disruption of plastidial localization. These findings pave the way for a better understanding of the prenylation of xanthones in plants and the identification of additional xanthone-specific prenyltransferases.
    MeSH term(s) Hypericum/genetics ; Hypericum/metabolism ; Dimethylallyltranstransferase/genetics ; Dimethylallyltranstransferase/metabolism ; Saccharomyces cerevisiae/genetics ; Saccharomyces cerevisiae/metabolism ; Xanthones/metabolism ; Xanthones/pharmacology ; Plant Extracts/pharmacology
    Chemical Substances prenyl ; Dimethylallyltranstransferase (EC 2.5.1.1) ; Xanthones ; Plant Extracts
    Language English
    Publishing date 2023-04-16
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 208914-2
    ISSN 1532-2548 ; 0032-0889
    ISSN (online) 1532-2548
    ISSN 0032-0889
    DOI 10.1093/plphys/kiad219
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Selective Functionalization of Microgels with Enzymes by Sortagging.

    Zou, Zhi / Gau, Elisabeth / El-Awaad, Islam / Jakob, Felix / Pich, Andrij / Schwaneberg, Ulrich

    Bioconjugate chemistry

    2019  Volume 30, Issue 11, Page(s) 2859–2869

    Abstract: Enzyme immobilization has been widely used to improve the stability and recyclability of enzymes in industrial processes. In this work, a sortase-mediated and therefore selective covalent immobilization strategy (sortagging) for enzymes on microgels ( ... ...

    Abstract Enzyme immobilization has been widely used to improve the stability and recyclability of enzymes in industrial processes. In this work, a sortase-mediated and therefore selective covalent immobilization strategy (sortagging) for enzymes on microgels (GelZyms) was investigated. Aqueous microgels were synthesized from poly(
    MeSH term(s) 6-Phytase/chemistry ; 6-Phytase/metabolism ; Aminoacyltransferases/chemistry ; Aminoacyltransferases/metabolism ; Bacteria/growth & development ; Bacteria/metabolism ; Bacterial Proteins/chemistry ; Bacterial Proteins/metabolism ; Cellulase/chemistry ; Cellulase/metabolism ; Cysteine Endopeptidases/chemistry ; Cysteine Endopeptidases/metabolism ; Enzymes, Immobilized/chemistry ; Enzymes, Immobilized/metabolism ; Laccase/chemistry ; Laccase/metabolism ; Lipase/chemistry ; Lipase/metabolism ; Microgels/chemistry ; Oxidoreductases/chemistry ; Oxidoreductases/metabolism
    Chemical Substances Bacterial Proteins ; Enzymes, Immobilized ; Microgels ; Oxidoreductases (EC 1.-) ; Laccase (EC 1.10.3.2) ; copper oxidase (EC 1.16.-) ; Aminoacyltransferases (EC 2.3.2.-) ; sortase A (EC 2.3.2.-) ; Lipase (EC 3.1.1.3) ; 6-Phytase (EC 3.1.3.26) ; Cellulase (EC 3.2.1.4) ; Cysteine Endopeptidases (EC 3.4.22.-)
    Language English
    Publishing date 2019-10-11
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1024041-x
    ISSN 1520-4812 ; 1043-1802
    ISSN (online) 1520-4812
    ISSN 1043-1802
    DOI 10.1021/acs.bioconjchem.9b00568
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: MicroGelzymes: pH-Independent Immobilization of Cytochrome P450 BM3 in Microgels.

    Nöth, Maximilian / Hussmann, Larissa / Belthle, Thomke / El-Awaad, Islam / Davari, Mehdi D / Jakob, Felix / Pich, Andrij / Schwaneberg, Ulrich

    Biomacromolecules

    2020  Volume 21, Issue 12, Page(s) 5128–5138

    Abstract: Microgels are an emerging class of "ideal" enzyme carriers because of their chemical and process stability, biocompatibility, and high enzyme loading capability. In this work, we synthesized a new type of permanently positively charged poly( ...

    Abstract Microgels are an emerging class of "ideal" enzyme carriers because of their chemical and process stability, biocompatibility, and high enzyme loading capability. In this work, we synthesized a new type of permanently positively charged poly(
    MeSH term(s) Bacillus megaterium ; Biocatalysis ; Cytochrome P-450 Enzyme System/metabolism ; Hydrogen-Ion Concentration ; Microgels ; Oxidation-Reduction
    Chemical Substances Microgels ; Cytochrome P-450 Enzyme System (9035-51-2)
    Language English
    Publishing date 2020-11-18
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1526-4602
    ISSN (online) 1526-4602
    DOI 10.1021/acs.biomac.0c01262
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Book ; Online ; Thesis: Cytochrome P450 enzymes involved in xanthone biosynthesis in Hypericum species

    El-Awaad, Islam Ahmed Mohamed [Verfasser] / Beerhues, Ludger [Akademischer Betreuer]

    2016  

    Author's details Islam Ahmed Mohamed El-Awaad ; Betreuer: Ludger Beerhues
    Keywords Biowissenschaften, Biologie ; Life Science, Biology
    Subject code sg570
    Language English
    Publisher Technische Universität Braunschweig
    Publishing place Braunschweig
    Document type Book ; Online ; Thesis
    Database Digital theses on the web

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  5. Article ; Online: Sequential regiospecific gem-diprenylation of tetrahydroxyxanthone by prenyltransferases from Hypericum sp.

    Nagia, Mohamed / Gaid, Mariam / Biedermann, Eline / Fiesel, Tobias / El-Awaad, Islam / Hänsch, Robert / Wittstock, Ute / Beerhues, Ludger

    The New phytologist

    2019  Volume 222, Issue 1, Page(s) 318–334

    Abstract: Polyprenylated acylphloroglucinol derivatives, such as xanthones, are natural plant products with interesting pharmacological properties. They are difficult to synthesize chemically. Biotechnological production is desirable but it requires an ... ...

    Abstract Polyprenylated acylphloroglucinol derivatives, such as xanthones, are natural plant products with interesting pharmacological properties. They are difficult to synthesize chemically. Biotechnological production is desirable but it requires an understanding of the biosynthetic pathways. cDNAs encoding membrane-bound aromatic prenyltransferase (aPT) enzymes from Hypericum sampsonii seedlings (HsPT8px and HsPTpat) and Hypericum calycinum cell cultures (HcPT8px and HcPTpat) were cloned and expressed in Saccharomyces cerevisiae and Nicotiana benthamiana, respectively. Microsomes and chloroplasts were used for functional analysis. The enzymes catalyzed the prenylation of 1,3,6,7-tetrahydroxyxanthone (1367THX) and/or 1,3,6,7-tetrahydroxy-8-prenylxanthone (8PX) and discriminated nine additionally tested acylphloroglucinol derivatives. The transient expression of the two aPT genes preceded the accumulation of the products in elicitor-treated H. calycinum cell cultures. C-terminal yellow fluorescent protein fusions of the two enzymes were localized to the envelope of chloroplasts in N. benthamiana leaves. Based on the kinetic properties of HsPT8px and HsPTpat, the enzymes catalyze sequential rather than parallel addition of two prenyl groups to the carbon atom 8 of 1367THX, yielding gem-diprenylated patulone under loss of aromaticity of the gem-dialkylated ring. Coexpression in yeast significantly increased product formation. The patulone biosynthetic pathway involves multiple subcellular compartments. The aPTs studied here and related enzymes may be promising tools for plant/microbe metabolic pathway engineering.
    MeSH term(s) Biocatalysis ; Chloroplasts/metabolism ; Dimethylallyltranstransferase/genetics ; Dimethylallyltranstransferase/metabolism ; Evolution, Molecular ; Gene Expression Regulation, Plant ; Hypericum/enzymology ; Hypericum/genetics ; Kinetics ; Phylogeny ; Plant Proteins/genetics ; Plant Proteins/metabolism ; RNA, Messenger/genetics ; RNA, Messenger/metabolism ; Stereoisomerism ; Xanthones/chemistry ; Xanthones/metabolism
    Chemical Substances 1,3,6,7-tetrahydroxyxanthone ; Plant Proteins ; RNA, Messenger ; Xanthones ; Dimethylallyltranstransferase (EC 2.5.1.1)
    Language English
    Publishing date 2019-01-05
    Publishing country England
    Document type Journal Article
    ZDB-ID 208885-x
    ISSN 1469-8137 ; 0028-646X
    ISSN (online) 1469-8137
    ISSN 0028-646X
    DOI 10.1111/nph.15611
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: A peptide-based coating toolbox to enable click chemistry on polymers, metals, and silicon through sortagging.

    Nöth, Maximilian / Zou, Zhi / El-Awaad, Islam / de Lencastre Novaes, Letícia C / Dilarri, Guilherme / Davari, Mehdi D / Ferreira, Henrique / Jakob, Felix / Schwaneberg, Ulrich

    Biotechnology and bioengineering

    2021  Volume 118, Issue 4, Page(s) 1520–1530

    Abstract: A versatile peptide-based toolbox for surface functionalization was established by a combination of a universal material binding peptide (LCI-anchor peptide) and sortase-mediated bioconjugation (sortagging). This toolbox facilitates surface ... ...

    Abstract A versatile peptide-based toolbox for surface functionalization was established by a combination of a universal material binding peptide (LCI-anchor peptide) and sortase-mediated bioconjugation (sortagging). This toolbox facilitates surface functionalization either as a one- or a two-step strategy. In the case of the one-step strategy, the desired functionality was directly introduced to LCI. For the two-step strategy, LCI was modified with a reactive group, which can be further functionalized (e.g., employing "click" chemistry). Sortagging of LCI, employing sortase A from Staphylococcus aureus, was achieved with six different amine compounds: dibenzocyclooctyne amine, biotin-polyethylene glycol amine, Cyanine-3 amine, kanamycin, methoxypolyethylene glycol amine (Mn = 5000 Da), and 2,2,3,3,4,4,4-Heptafluorobutylamine. The purification of LCI-amine sortagging products was performed by a negative purification using Strep-tag II affinity chromatography, resulting in LCI-amine conjugates with purities >90%. For the two-step strategy, the LCI-dibenzocyclooctyne sortagging product was purified and enabled, through copper-free azide-alkyne "click" chemistry, universal surface functionalization of material surfaces such as polypropylene, polyethylene terephthalate, stainless steel, gold, and silicon. The click reaction was performed before or after surface binding of LCI-dibenzocyclooctyne. Finally, in the case of the one-step strategy, polypropylene was directly functionalized with Cyanine-3 and biotin-polyethylene glycol amine.
    MeSH term(s) Aminoacyltransferases/chemistry ; Bacterial Proteins/chemistry ; Click Chemistry ; Coated Materials, Biocompatible/chemical synthesis ; Coated Materials, Biocompatible/chemistry ; Cysteine Endopeptidases/chemistry ; Metals/chemistry ; Peptides/chemistry ; Polymers/chemistry ; Silicon/chemistry ; Staphylococcus aureus/enzymology
    Chemical Substances Bacterial Proteins ; Coated Materials, Biocompatible ; Metals ; Peptides ; Polymers ; Aminoacyltransferases (EC 2.3.2.-) ; sortase A (EC 2.3.2.-) ; Cysteine Endopeptidases (EC 3.4.22.-) ; Silicon (Z4152N8IUI)
    Language English
    Publishing date 2021-02-04
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 280318-5
    ISSN 1097-0290 ; 0006-3592
    ISSN (online) 1097-0290
    ISSN 0006-3592
    DOI 10.1002/bit.27666
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Bifunctional CYP81AA proteins catalyse identical hydroxylations but alternative regioselective phenol couplings in plant xanthone biosynthesis.

    El-Awaad, Islam / Bocola, Marco / Beuerle, Till / Liu, Benye / Beerhues, Ludger

    Nature communications

    2016  Volume 7, Page(s) 11472

    Abstract: Xanthones are natural products present in plants and microorganisms. In plants, their biosynthesis starts with regioselective cyclization of 2,3',4,6-tetrahydroxybenzophenone to either 1,3,5- or 1,3,7-trihydroxyxanthones, catalysed by cytochrome P450 ( ... ...

    Abstract Xanthones are natural products present in plants and microorganisms. In plants, their biosynthesis starts with regioselective cyclization of 2,3',4,6-tetrahydroxybenzophenone to either 1,3,5- or 1,3,7-trihydroxyxanthones, catalysed by cytochrome P450 (CYP) enzymes. Here we isolate and express CYP81AA-coding sequences from Hypericum calycinum and H. perforatum in yeast. Microsomes catalyse two consecutive reactions, that is, 3'-hydroxylation of 2,4,6-trihydroxybenzophenone and C-O phenol coupling of the resulting 2,3',4,6-tetrahydroxybenzophenone. Relative to the inserted 3'-hydroxyl, the orthologues Hc/HpCYP81AA1 cyclize via the para position to form 1,3,7-trihydroxyxanthone, whereas the paralogue HpCYP81AA2 directs cyclization to the ortho position, yielding the isomeric 1,3,5-trihydroxyxanthone. Homology modelling and reciprocal mutagenesis reveal the impact of S375, L378 and A483 on controlling the regioselectivity of HpCYP81AA2, which is converted into HpCYP81AA1 by sextuple mutation. However, the reciprocal mutations in HpCYP81AA1 barely affect its regiospecificity. Product docking rationalizes the alternative C-O phenol coupling reactions. Our results help understand the machinery of bifunctional CYPs.
    MeSH term(s) Amino Acid Sequence ; Biocatalysis ; Biosynthetic Pathways/genetics ; Cells, Cultured ; Cytochrome P-450 Enzyme System/chemistry ; Cytochrome P-450 Enzyme System/genetics ; Cytochrome P-450 Enzyme System/metabolism ; Hydroxylation ; Hypericum/cytology ; Hypericum/enzymology ; Hypericum/genetics ; Molecular Docking Simulation ; Mutation ; Phenol/chemistry ; Phenol/metabolism ; Plant Proteins/chemistry ; Plant Proteins/genetics ; Plant Proteins/metabolism ; Sequence Homology, Amino Acid ; Stereoisomerism ; Xanthones/chemistry ; Xanthones/metabolism
    Chemical Substances Plant Proteins ; Xanthones ; Phenol (339NCG44TV) ; Cytochrome P-450 Enzyme System (9035-51-2)
    Language English
    Publishing date 2016-05-05
    Publishing country England
    Document type Journal Article
    ISSN 2041-1723
    ISSN (online) 2041-1723
    DOI 10.1038/ncomms11472
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  8. Article ; Online: Molecular Cloning and Characterization of a Xanthone Prenyltransferase from Hypericum calycinum Cell Cultures.

    Fiesel, Tobias / Gaid, Mariam / Müller, Andreas / Bartels, Joana / El-Awaad, Islam / Beuerle, Till / Ernst, Ludger / Behrends, Sönke / Beerhues, Ludger

    Molecules (Basel, Switzerland)

    2015  Volume 20, Issue 9, Page(s) 15616–15630

    Abstract: In plants, prenylation of metabolites is widely distributed to generate compounds with efficient defense potential and distinct pharmacological activities profitable to human health. Prenylated compounds are formed by members of the prenyltransferase (PT) ...

    Abstract In plants, prenylation of metabolites is widely distributed to generate compounds with efficient defense potential and distinct pharmacological activities profitable to human health. Prenylated compounds are formed by members of the prenyltransferase (PT) superfamily, which catalyze the addition of prenyl moieties to a variety of acceptor molecules. Cell cultures of Hypericum calycinum respond to elicitor treatment with the accumulation of the prenylated xanthone hyperxanthone E. A cDNA encoding a membrane-bound PT (HcPT) was isolated from a subtracted cDNA library and transcript preparations of H. calycinum. An increase in the HcPT transcript level preceded hyperxanthone E accumulation in cell cultures of H. calycinum treated with elicitor. The HcPT cDNA was functionally characterized by expression in baculovirus-infected insect cells. The recombinant enzyme catalyzed biosynthesis of 1,3,6,7-tetrahydroxy-8-prenylxanthone through regiospecific C-8 prenylation of 1,3,6,7-tetrahydroxyxanthone, indicating its involvement in hyperxanthone E formation. The enzymatic product shared significant structural features with the previously reported cholinesterase inhibitor γ-mangostin. Thus, our findings may offer a chance for semisynthesis of new active agents to be involved in the treatment of Alzheimer's disease.
    MeSH term(s) Cloning, Molecular/methods ; Dimethylallyltranstransferase/chemistry ; Dimethylallyltranstransferase/genetics ; Dimethylallyltranstransferase/metabolism ; Gene Library ; Hypericum/enzymology ; Hypericum/genetics ; Models, Molecular ; Plant Proteins/chemistry ; Plant Proteins/genetics ; Plant Proteins/metabolism ; Protein Conformation ; Recombinant Proteins/chemistry ; Recombinant Proteins/genetics ; Recombinant Proteins/metabolism ; Xanthones/metabolism
    Chemical Substances Plant Proteins ; Recombinant Proteins ; Xanthones ; Dimethylallyltranstransferase (EC 2.5.1.1)
    Language English
    Publishing date 2015-08-27
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1413402-0
    ISSN 1420-3049 ; 1431-5165 ; 1420-3049
    ISSN (online) 1420-3049
    ISSN 1431-5165 ; 1420-3049
    DOI 10.3390/molecules200915616
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