A5043435997- Natural Compound Pharmacology Studies
- Plant biochemistry and biosynthesis
- Plant Gene Expression Analysis
- Plant tissue culture and regeneration
- Plant Pathogens and Fungal Diseases
- Plant Molecular Biology Research
- Phytochemicals and Antioxidant Activities
- Plant Physiology and Cultivation Studies
- Plant-Microbe Interactions and Immunity
- Polysaccharides and Plant Cell Walls
- Garlic and Onion Studies
- Biochemical and biochemical processes
- Phytochemistry and Biological Activities
- Bioactive natural compounds
- Legume Nitrogen Fixing Symbiosis
- Horticultural and Viticultural Research
- Allelopathy and phytotoxic interactions
- Plant Pathogenic Bacteria Studies
- Phytochemistry and biological activity of medicinal plants
- Fermentation and Sensory Analysis
- Fungal Plant Pathogen Control
- Plant Disease Management Techniques
- GABA and Rice Research
- Polyamine Metabolism and Applications
- Carbohydrate Chemistry and Synthesis
Technische Universität Braunschweig
2015-2025
Julius Kühn-Institut
2011
University of Bonn
1991-2001
Max Planck Society
1993-1994
University of Münster
1988-1993
Institut für Forensische Genetik
1985
Benzophenone derivatives, such as polyprenylated benzoylphloroglucinols and xanthones, are biologically active secondary metabolites. The formation of their C13 skeleton is catalyzed by benzophenone synthase (BPS; EC 2.3.1.151) that has been cloned from cell cultures Hypericum androsaemum. BPS a novel member the superfamily plant polyketide synthases (PKSs), also termed type III PKSs, with 53-63% amino acid sequence identity. Heterologously expressed was homodimer subunit molecular mass 42.8...
Biphenyls and dibenzofurans are the phytoalexins of Pyrinae, a subtribe plant family Rosaceae. The Pyrinae correspond to long-recognized Maloideae. Economically valuable species apples pears. formed de novo in response infection by bacterial fungal pathogens. inducible defense compounds were also produced cell suspension cultures after treatment with biotic abiotic elicitors. antimicrobial activity was demonstrated. To date, 10 biphenyls 17 isolated from 14 30 genera. most widely distributed...
Abstract Although a number of plant natural products are derived from benzoic acid, the biosynthesis this structurally simple precursor is poorly understood. Hypericum calycinum cell cultures accumulate acid-derived xanthone phytoalexin, hyperxanthone E, in response to elicitor treatment. Using subtracted complementary DNA (cDNA) library and sequence information about conserved coenzyme A (CoA) ligase motifs, cDNA encoding cinnamate:CoA (CNL) was isolated. This enzyme channels metabolic flux...
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 express CYP81AA-coding sequences from Hypericum calycinum H. perforatum yeast. Microsomes catalyse two consecutive reactions, that is, 3'-hydroxylation 2,4,6-trihydroxybenzophenone C-O phenol coupling the resulting...
A soil- and site-dependent complex of diverse microbial populations causes apple replant disease (ARD), which leads to economic losses for tree nurseries producers due reduced plant growth diminished fruit yields. Soil fumigation has been widely used mitigate ARD, but the application these chemicals is restricted in European Union. Hence, other counteractions have be developed. Genomics-based breeding may select ARD-tolerant genotypes; however, molecular responses ARD are not well...
A soil column split-root experiment was designed to investigate the ability of apple replant disease (ARD)-causing agents spread in soil. 'M26' rootstocks grew into a top layer Control soil, followed by barrier-free split-soil (Control soil/ARD soil). We observed severely reduced root growth, concomitant with enhanced gene expression phytoalexin biosynthetic genes and content roots from ARD indicating pronounced local plant defense response. Amplicon sequencing (bacteria, archaea, fungi)...
The Rosaceous subtribe Pyrinae (formerly subfamily Maloideae) is well-known for its economically important fruit trees, such as apple and pear, also includes Sorbus aucuparia. Elicitor-treated S. aucuparia cell cultures are used to study the biosynthesis of Pyrinae-specific phytoalexins, biphenyls dibenzofurans. Three (aucuparin, noraucuparin, 2′-hydroxyaucuparin) a dibenzofuran (eriobofuran) were isolated structure elucidated using GC-MS NMR. A second low abundance was tentatively assigned...
A comparative study was carried out with ethanolic (80%) extracts from leaves and cell cultures of three Callistemon species, namely C. lanceolatus (CL), viridiflorous (CV), comboynensis (CC). Cell suspensions the species were grown in liquid Murashige Skoog (MS) medium (100 ml) supplemented 0.9 mg·g-1 kinetin combination 1.1 NAA. The CL leaf extract standardized to contain highest amount phenolics (104 ± 2.0 mg·g-1), followed by CC (95.8 1.2 mg·g-1) CV (79.8 4.6 mg·g-1). On other hand,...
Summary Xanthones are specialized metabolites with antimicrobial properties, which accumulate in roots of Hypericum perforatum . This medicinal plant provides widely taken remedies for depressive episodes and skin disorders. Owing to the array pharmacological activities, xanthone derivatives attract attention drug design. Little is known about sites biosynthesis accumulation xanthones roots. Xanthone localized at transcript, protein, product levels using situ mRNA hybridization, indirect...
Sulfur for fire: The molecular basis the biosynthesis of antimetabolite 6-thioguanine (6TG) was unveiled in Erwinia amylovora, causative agent fire blight. Bioinformatics, heterologous pathway reconstitution E. coli, and mutational analyses indicate that protein YcfA mediates guanine thionation analogy to 2-thiouridylase. Assays planta cell cultures reveal first time a crucial role 6TG blight pathogenesis.
Apple replant disease (ARD) is a severe problem in apple production worldwide. It caused by complex of soil biota, leading to small discolorated roots, as well increased biosynthesis phytoalexins, total phenolic compounds and antioxidants. We sampled from randomized field plots with either trees affected ARD, which were five times replanted every second year, or healthy growing plots, had grass cover during this period. investigated the contribution nematodes ARD dissecting biota infested...
Apple replant disease (ARD) is a soil-borne disease, which of particular importance for fruit tree nurseries and growers. The manifests by poor vegetative development, stunted growth, reduced yield in terms quantity quality, if apple plants (usually rootstocks) are replanted several times at the same site. Genotype-specific differences reaction to ARD documented, but less known about genetic mechanisms behind this symptomatology. Recent transcriptome analyses resulted number candidate genes...
Microshoot agitated and bioreactor cultures (PlantForm bioreactors) of three Hypericum perforatum cultivars (Elixir, Helos, Topas) were maintained in four variants Murashige Skoog medium (MS) supplemented with 6-benzylaminopurine (BAP) 1-naphthaleneacetic acid (NAA) (in the range 0.1-3.0 mg/L). In both types vitro cultures, accumulation dynamics phenolic acids, flavonoids, catechins investigated during 5- 4-week growth cycles, respectively. The contents metabolites methanolic extracts from...
Apple replant disease (ARD) is a problem in apple tree and fruit production worldwide its etiology not fully understood. This study aimed to evaluate the tolerance of six genotypes, including susceptible rootstock 'M.26', three potentially tolerant rootstocks 'EMR.2', 'G.202' 'G.935', two genebank accessions Malus spectabilis MAL0130 sargentii MAL0739 ARD soils from sites. Using greenhouse biotest, plants were grown for 56 days or respective γ-irradiated soil. No genotype showed consistent...
A central step in xanthone biosynthesis is the formation of C 13 skeleton, i.e. an intermediate benzophenone. Biosynthesis 2,3′,4,6‐tetrahydroxybenzophenone from m ‐hydroxybenzoyl‐CoA and malonyl‐CoA was shown cell‐free extracts cultured cells Centaurium erythraea . The enzyme catalyzing this reaction named benzophenone synthase.