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Fig. 5 in Metabolic adaptation of diatoms to hypersalinity
No full textFig. 5. Venn diagrams for significantly dysregulated compounds of all identification levels for P. tricornutum (blue), T. pseudonana (green), and S. marinoi (yellow) detected with LC-MS at 24 h (A) and 96 h (B) after the salinity stress. The percentage of the total number of compounds detected for all three algae is given and numbers in brackets indicate the amount of compounds. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)Published as part of Nikitashina, Vera, Stettin, Daniel & Pohnert, Georg, 2022, Metabolic adaptation of diatoms to hypersalinity, pp. 113267 in Phytochemistry 201 on page 8, DOI: 10.1016/j.phytochem.2022.113267, http://zenodo.org/record/694427
Fig. 2. Pairwise PCA plots for P. tricornutum endometabolome samples extracted 24 in Metabolic adaptation of diatoms to hypersalinity
No full textFig. 2. Pairwise PCA plots for P. tricornutum endometabolome samples extracted 24 (A, B) and 96 (C, D) hours after the salinity stress treatment. PCA plots of all data analyzed together (E, F). Panels A, C, and E show results from GC-MS. Panels B, D, and F result from the analysis of LC-MS data; the number of replicates analyzed is 5. (For interpretation of the colours in this figure legend, the reader is referred to the Web version of this article.)Published as part of Nikitashina, Vera, Stettin, Daniel & Pohnert, Georg, 2022, Metabolic adaptation of diatoms to hypersalinity, pp. 113267 in Phytochemistry 201 on page 5, DOI: 10.1016/j.phytochem.2022.113267, http://zenodo.org/record/694427
Fig. 3. Pairwise PCA plots for S. marinoi endometabolome samples extracted 24 in Metabolic adaptation of diatoms to hypersalinity
No full textFig. 3. Pairwise PCA plots for S. marinoi endometabolome samples extracted 24 (A, B) and 96 (C, D) hours after the salinity stress treatment. PCA plots of all data analyzed together (E, F). Panels A, C, and E show results from GC-MS. Panels B, D, and F result from the analysis of LC-MS data; the number of replicates analyzed is 4–5 (see Experimental 5.13.). (For interpretation of the colours in this figure legend, the reader is referred to the Web version of this article.)Published as part of Nikitashina, Vera, Stettin, Daniel & Pohnert, Georg, 2022, Metabolic adaptation of diatoms to hypersalinity, pp. 113267 in Phytochemistry 201 on page 7, DOI: 10.1016/j.phytochem.2022.113267, http://zenodo.org/record/694427
Fig. 5 in Metabolic adaptation of diatoms to hypersalinity
No full textFig. 5. Venn diagrams for significantly dysregulated compounds of all identification levels for P. tricornutum (blue), T. pseudonana (green), and S. marinoi (yellow) detected with LC-MS at 24 h (A) and 96 h (B) after the salinity stress. The percentage of the total number of compounds detected for all three algae is given and numbers in brackets indicate the amount of compounds. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)Published as part of <i>Nikitashina, Vera, Stettin, Daniel & Pohnert, Georg, 2022, Metabolic adaptation of diatoms to hypersalinity, pp. 1-13 in Phytochemistry (113267) 201</i> on page 8, DOI: 10.1016/j.phytochem.2022.113267, <a href="http://zenodo.org/record/10125527">http://zenodo.org/record/10125527</a>
Fig. 1. Pairwise PCA plots for T. pseudonana endometabolome samples extracted 24 in Metabolic adaptation of diatoms to hypersalinity
No full textFig. 1. Pairwise PCA plots for T. pseudonana endometabolome samples extracted 24 (A, B) and 96 (C, D) hours after salinity increase. PCA plots of all data analyzed together (E, F). Panels A, C, and E show results from GC-MS. Panels B, D, and F result from the analysis of LC-MS data; the number of replicates analyzed is 4–5 (see Experimental 5.13.). (For interpretation of the colours in this figure legend, the reader is referred to the Web version of this article.)Published as part of <i>Nikitashina, Vera, Stettin, Daniel & Pohnert, Georg, 2022, Metabolic adaptation of diatoms to hypersalinity, pp. 1-13 in Phytochemistry (113267) 201</i> on page 3, DOI: 10.1016/j.phytochem.2022.113267, <a href="http://zenodo.org/record/10125527">http://zenodo.org/record/10125527</a>
Fig. 4 in Metabolic adaptation of diatoms to hypersalinity
No full textFig. 4. Venn diagrams for significantly dysregulated compounds of all identification levels for P. tricornutum (blue), T. pseudonana (green), and S. marinoi (yellow) detected with GC-MS at 24 h (A) and 96 h (B) after the salinity stress. The percentage of the total number of compounds detected for all three algae is given and numbers in brackets indicate the amount of compounds. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)Published as part of Nikitashina, Vera, Stettin, Daniel & Pohnert, Georg, 2022, Metabolic adaptation of diatoms to hypersalinity, pp. 113267 in Phytochemistry 201 on page 8, DOI: 10.1016/j.phytochem.2022.113267, http://zenodo.org/record/694427
Neomeris annulata Dickie 1874
No full text<i>2.3. Sulfated metabolites of N. annulata</i> <p> In <i>N. annulata</i> we detected two closely eluting metabolites, with identical pseudomolecular ions of [M–H] – = 259 and each with a fragment of [M–H–80] –. These metabolites were not detectable anymore shortly after wounding. Molecular weight and MS/MS spectra would be in accordance with a mono sulfated dihydroxycinnamic acid, such as caffeic acid or a positional isomer. We therefore synthesized the sulfated 3,4-, 2,3-, 2,4- and 2,5 dihydroxycinnamic acid derivatives, but despite very similar retention times and MS/MS fragmentation patterns identity to the natural products could not be confirmed.</p>Published as part of <i>Kurth, Caroline, Welling, Matthew & Pohnert, Georg, 2015, Sulfated phenolic acids from Dasycladales siphonous green algae, pp. 417-423 in Phytochemistry 117</i> on page 418, DOI: 10.1016/j.phytochem.2015.07.010, <a href="http://zenodo.org/record/10486436">http://zenodo.org/record/10486436</a>
Cymopolia barbata J. V. Lamouroux 1816
No full text<i>2.2. Sulfated metabolites of C. barbata</i> <p> In <i>C. barbata</i> chromatograms two dominant signals exhibiting an [M–H–80] – fragment were observed. Retention times and mass spectra were in accordance with dihydroxycoumarin sulfate and SBA. Co-injection experiments as described above proved these structural suggestions (Fig. 3). In the extracts of slightly stressed algae we could still detect the ions corresponding to SBA and dihydroxycoumarin sulfate. We also found trihydroxycoumarin indicative for a wound activated desulfatation, a mechanism previously shown to control wound plug formation of <i>D. vermicularis</i> (Fig. 1) (Welling et al., 2011). In addition in non-stressed algal material extracted directly after harvesting we observed a signal with a molecular ion of 289 [M–H] – (data not shown) that also exhibited the loss of 80, which would be in accordance with a methoxylated dihydroxycoumarin sulfate.</p>Published as part of <i>Kurth, Caroline, Welling, Matthew & Pohnert, Georg, 2015, Sulfated phenolic acids from Dasycladales siphonous green algae, pp. 417-423 in Phytochemistry 117</i> on page 418, DOI: 10.1016/j.phytochem.2015.07.010, <a href="http://zenodo.org/record/10486436">http://zenodo.org/record/10486436</a>
Dasycladus vermicularis Krasser 1898
No full text<i>2.1. Sulfated metabolites of D. vermicularis</i> <p> <b>⇑</b> Corresponding author. <i>E-mail address:</i> [email protected] (G. Pohnert).</p> <p> Three candidate molecules for which sulfatation was indicated by the presence of a fragment of [M–H–80] – in the mass spectrum were detected by UPLC–MS/MS measurements in extracts of <i>D. vermicularis</i>. The metabolite with a mass of 273 [M–H] – and a fragment with <i>m</i> / <i>z</i> = 193 could readily be assigned to dihydroxycoumarin sulfate (Fig. 1) based on previous results and co-injection with a synthetic standard (Welling et al., 2009). For identification of the two unknown potentially sulfated metabolites (<i>m</i> / <i>z</i> = 217 [M–H] – and 231 [M–H] –, respectively) synthetic standards were prepared. Based on mass spectra and polarity in UPLC–MS (Fig. 2A, D and F) we selected 4-(sulfooxy)benzoic acid (SBA) and 4-(sulfooxy)phenylacetic acid (SPA) as likely candidates. After estimation of the content of the metabolites in the algal extract, co-injection experiments with algal extract and the synthetic standards were performed (Fig. 2C and E). Peak symmetry was important since the short retention times and strong solvent effects of the samples required a rigorous quality control of co-eluting peaks. SBA showed the same retention time and mass spectrum to the first sulfated metabolite in the <i>D. vermicularis</i> extract. When added in co-injection experiments, an increase of intensity of the first signal was observed (Fig. 2C). The mass spectrum remained unaffected by the co-injection. The <i>ortho</i> - and <i>meta</i> -isomers of (sulfooxy)benzoic acid eluted at different retention times (data not shown). The same procedure was applied for co-injection of SPA (Fig. 2E). No significant change in peak symmetry was observed upon addition of SBA or SPA, which unambiguously confirms the identity of the natural and synthetic products. Besides the occurrence as catabolic products in mouse urine, these metabolites have to our knowledge not been reported as natural products before (Manna et al., 2011; van der Hooft et al., 2012).</p>Published as part of <i>Kurth, Caroline, Welling, Matthew & Pohnert, Georg, 2015, Sulfated phenolic acids from Dasycladales siphonous green algae, pp. 417-423 in Phytochemistry 117</i> on page 417, DOI: 10.1016/j.phytochem.2015.07.010, <a href="http://zenodo.org/record/10486436">http://zenodo.org/record/10486436</a>
Sulfated phenolic acids as readily activatable storage forms of antifouling agents in marine plants
Full text linkZosteric acid (ZS) has recently been discussed as a potent, natural biofilm inhibiting agent. Previously to this work have further sulfated metabolites of marine origin been detected, presumably structurally related to ZS. For identification of these unknown metabolites, pure standards were synthesized and the assumed compounds 4-(sulfooxy)benzoic acid (BS) and 4-(sulfooxy)-phenylacetic acid (AS) confirmed by UPLC-MS (Ultra high performance liquid chromatography-mass spectrometry) experiments. The structural relation of AS and BS to ZS encouraged to investigate, if these would exhibit similar properties as ZS and which structural elements define their activity. The combination of different bioassays and test organisms (Escherichia coli, Vibrio natriegens), UPLC-MS stability screening of the test compounds and monitoring of the impact on bacterial growth, provided a comprehensive overview of the activity of sulfated phenolic acids in comparison to their non-sulfated forms. Impacts of the test compounds were species dependent and influenced by the experimental setup. Still, some common conclusions could be drawn. In neither of the employed assays could the previously suggested antifouling activity of ZS be confirmed, nor any effect observed from AS and BS. Instead, the non-sulfated form of ZS, 4-hydroxy-cinnamic acid (Z), proved highly efficient to inhibit bacterial settlement. UPLC-MS measurements revealed sulfatase activity in V. natriegens, leading to an in situ release of the active, non-sulfated form Z into the bacterial medium. The non-sulfated forms of AS and BS (A, B) showed either only a short term effect on biofilm inhibition (B), or none (A). The influence of Z on bacterial growth was both concentration and species dependent. The common consent concerning the activity of ZS could be revised. The sulfate ester seems thus to constitute a storage form of the active compound Z
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