A paradigm regarding rhamnogalacturonans II (RGII) is their strictly conserved structure within a given plant. We developed and employed fast structural characterization method based on chromatography mass spectrometry, allowing analysis of RGII side chains from microgram amounts cell wall. found that structures are much more diverse than so far described. In chain wild-type plants, up to 45% the l-fucose substituted by l-galactose, state seemingly uncorrelated with dimerization capacity....

The filamentous fungus Trichoderma reesei is a prolific producer of plant cell wall degrading enzymes, which are regulated in response to diverse environmental signals for optimal adaptation, but also produces wide array secondary metabolites. Available carbon source and light the strongest cues currently known impact secreted enzyme levels an interplay with regulation metabolism became increasingly obvious recent years. While cellulase already be modulated by different mitogen activated...

Abstract Phosphorylated carbohydrates are important intracellular metabolites and thus of prime interest in metabolomics research. Complications their analysis arise from the existence structural isomers that do have similar fragmentation patterns MS/MS hard to resolve chromatographically. Herein, we present selective methods for liquid chromatographic separation sugar phosphates, such as hexose pentose 2‐ 3‐phosphoglycerate, dihydroxyacetone phosphate glyceraldehyde 3‐phosphate, well...

The toxicity of acetylacetone has been demonstrated in various studies. Little is known, however, about metabolic pathways for its detoxification or mineralization. Data presented here describe the first time microbial degradation and characterization a novel enzyme that initiates pathway. From an Acinetobacter johnsonii strain grew with as sole carbon source, inducible acetylacetone-cleaving was purified to homogeneity. corresponding gene, coding 153 amino acid sequence does not show any...

Abstract High‐resolution NMR spectroscopy is a fast and accurate tool to measure the content of n ‐3 PUFA in unoxidised oils. Four types fish oils with high amount were oxidised under different conditions, changes their fatty acid pattern monitored compared traditional analytical methods, especially GC. Good compliances obtained for at early oxidation stages. Distinct signals or signal ratio intensities arose only higher‐oxidised that irradiated heated presence oxygen over several days....

Heck-type 4-exo-trig cyclization of linear 2-enol triflate-1,5-hexadienes provides functionalized methylene cyclobutanes. Intramolecular palladium coordination can initiate β-hydride elimination leading to 1,2-dimethylene cyclobutane derivatives, which are obtained with high selectivity if substrates having a geminal diphenyl group at Cα used. In parallel, formal 5-endo-trig and form 1-methylene cyclopent-2-en derivatives.

Abstract A series of cationic gemini surfactants containing different spacer length were synthesized and analyzed structurally. It was shown that the surface tension (σ) critical micelle concentration (CMC), which had a maximum for n ‐C 4 H 8 depended on length. The foaming ability foam stability are high with short spacers (C 2 to ), while longer lead distinct decrease these parameters. Foaming properties discussed in terms configuration conformation surfactant molecule relation...

The N-glycosylation of the model nematode Caenorhabditis elegans has proven to be highly variable and rather complex; it is an example contradict existing impression that "simple" organisms possess also a simple glycomic capacity. In previous studies in number laboratories, N-glycans with up four fucose residues have been detected. However, although linkage three N,N′-diacetylchitobiosyl core by structural enzymatic analyses, nature fourth remained uncertain. By constructing triple mutant...

Alstrostine A and isoalstrostine are monoterpenoid indole alkaloid glycosides with unique structures found in the plant families Apocynaceae Rubiaceae. With molecular weights exceeding 900, nine chiral centers (excluding sugar rings), complex fused‐ring structures, structural elucidation of these molecules using spectral analysis is highly challenging. Therefore, their identification through total synthesis important both natural product chemistry synthetic organic chemistry. In this study,...

Hydrogen bonding is important in cellulosic and other carbohydrate structures, but the role of interactions between nonpolar groups less understood. Therefore, we synthesized cyclohexyl 4′-O-cyclohexyl β-d-cellobioside (8), a molecule that has two glucose rings rings. Key to attaching group was making 4′-O,6′-O-cyclohexylidene ketal. After peracetylation, cyclohexylidene ketal ring opened regioselectively, providing 65% 8 after final deacetylation. Comparison crystal structure 8, as...

L-fucose is a common constituent of Asn-linked glycans in vertebrates, invertebrates, and plants, but fungal glycoproteins, fucose has not been found so far. However, by mass spectrometry we detected N-glycans O-glycans containing one to six deoxyhexose residues fruit bodies several basidiomycetes. The chanterelles (Cantharellus cibarius) contained chromatographically identical sensitive α-L-fucosidase. Analysis individual glycan species tandem MS, glycosidase digestion, finally (1)H NMR...

On the basis of a comparison 42 Stemona samples, representing eight different species collected and cultivated in Thailand, species-specific accumulation trends alkaloids were analyzed. An overview was achieved by comparative HPLC analyses methanolic crude extracts underground parts coupled with diode array or evaporative light scattering detectors. All major compounds isolated their structures elucidated NMR MS analyses. Protostemonine- stichoneurine-type derivatives dominated, from which...

Abstract Background Trichoderma reesei represents a model system for investigation of plant cell wall degradation and its connection to light response. The cyclic adenosine monophosphate pathway (cAMP pathway) plays an important role in both physiological outputs, being crucial regulation photoreceptor function as well cellulase on different carbon sources. Phosphorylation photoreceptors the catabolite repressor CRE1 was shown ascomycetes, indicating relevance protein kinase A target genes...

Abstract Two novel protoilludane sesquiterpenoids, named pasteurestins A and B ( 1 2 ), were disclosed in a recent patent. These compounds reported to exhibit strong selective activity against some Mannheimia haemolytica strains, pathogen causatives for bovine respiratory disease. properties qualified as potential lead structures new veterinary antibiotics; however, neither the absolute nor relative configurations had been determined, available any longer. We thus developed total syntheses...

The extent of DNA decompaction induced by<italic>m-s-m</italic>gemini surfactants depend on the surfactant's tail length and spacer's length.