8 research outputs found
A new 3-alkylpyridine alkaloid from the marine sponge <i>Haliclona</i> sp. and its cytotoxic activity
<p>A new alkaloid, 3-dodecyl pyridine containing a terminal cyano group (<b>1</b>), was isolated from the methanol extract of an Indonesia marine sponge <i>Haliclona</i> sp. Its chemical structure was determined by a combination of spectroscopic methods, including 1D and 2D NMR. Bioassay results indicated that compound <b>1</b> had moderate cytotoxity against tumour cell lines A549, MCF-7 and Hela with IC<sub>50</sub> values of 41.8, 48.4 and 33.2Â ÎŒM, respectively.</p
Accurate mass analysis on a <10 ”g sample: The actinâbound biosynthetic products were isolated from a sample (code: ACâXâA) via the procedure shown in Figure 3, Step 4.
<p>The top panel shows, by Total Ion Chromatogram (TIC) areas, three compounds of interest observed in a ratio of 37â¶54â¶9 from this material. The three lower panels show AMâMS data for dereplication of compounds at: 2.34 minâ=âjasplakinolide C (<b>2</b>), 2.47 minâ=âjasplakinolide B (<b>3</b>), and 2.85 minâ=âjasplakinolide (<b>1</b>), respectively.</p
Accurate mass analysis on a <10 ”g sample: The actinâbound biosynthetic products were isolated from a sample (code: ACâXâA) via the procedure shown in Figure 3, Step 4.
<p>The top panel shows, by Total Ion Chromatogram (TIC) areas, three compounds of interest observed in a ratio of 37â¶54â¶9 from this material. The three lower panels show AMâMS data for dereplication of compounds at: 2.34 minâ=âjasplakinolide C (<b>2</b>), 2.47 minâ=âjasplakinolide B (<b>3</b>), and 2.85 minâ=âjasplakinolide (<b>1</b>), respectively.</p
Deployments.
<p>Date, extract name, location, depth, time of inoculation (T<sub>I</sub>) and time of incubation (T<sub>C</sub>) for the 11 deployments explored in this program. Three expeditions were conducted between the period of 05/02/2011 and 07/31/2011 at three locations. Deployment 6 was lost at sea.</p
A sponge based hypothesis.
<p>A sideâbyâside comparison of the three natural products shown here illustrates an example of parallel biosynthetic pathways that operated in disparate organisms including marine sponges and myxobacteria. These compounds, arising from the fusion of a triketide with unusual tripeptide moieties, represent the types of biosynthetic products targeted in this study owing to their parallel biogenetic and potential microbial origins. Each compound was previously discovered from the indicated source organisms, and all were subsequently shown to be Fâactin stabilizers.</p
<i>In Situ</i> Natural Product Discovery via an Artificial Marine Sponge
<div><p>There is continuing international interest in exploring and developing the therapeutic potential of marineâderived small molecules. Balancing the strategies for ocean based sampling of source organisms versus the potential to endanger fragile ecosystems poses a substantial challenge. In order to mitigate such environmental impacts, we have developed a deployable artificial sponge. This report provides details on its design followed by evidence that it faithfully recapitulates traditional natural product collection protocols. Retrieving this artificial sponge from a tropical ecosystem after deployment for 320 hours afforded three actinâtargeting jasplakinolide depsipeptides that had been discovered two decades earlier using traditional sponge specimen collection and isolation procedures. The successful outcome achieved here could reinvigorate marine natural products research, by producing new environmentally innocuous sources of natural products and providing a means to probe the true biosynthetic origins of complex marineâderived scaffolds.</p></div
A schematic overview.
<p>The artificial sponge was mounted underwater proximal to sponges envisioned to be engaged in secondary metabolite biosynthesis, such as shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0100474#pone-0100474-g001" target="_blank">Figure 1</a>. Its components are: particle filters (disposable funnel containing a polyethylene frit, OPâ6602â14, ChemGlass), microbial filters (2 ”m pore, 50 mm OD, MillexâAP microbial filters, SLA05010, Millipore); a SeaBattery (DeepSea Power & Light); a power supply (selfâbuilt); a microdiaphram pump (NF5RP, KNF Neuberger); a hollowâfiber bioreactor (4300âC5011, FiberCell Systems); and parallelâbundle of sepâpak cartridges (ePlastics) containing Amberlite XADâ18 resin (Dow Chemicals). The hollowâfiber bioreactor can act as a bioreactor allowing microbial material to culture inside the artificial sponge. The sepâpak cartridges serve to collect materials either from the seawater or from the microbial content within the hollowâfiber bioreactor. Green arrows indicate flow direction during charging of the hollowâfiber bioreactor from the water column during the inoculation stage (step 1, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0100474#pone-0100474-g003" target="_blank">Figure 3</a>). Blue arrows depict the passage of seawater through the artificial sponge during the incubation stage (step 2, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0100474#pone-0100474-g003" target="_blank">Figure 3</a>). A generic depiction of the anatomy of a sponge is shown within the inset to illustrate the parallel engineered design, codes are: osâ=âosculum, spcâ=âspongocoel, chcâ=âchoanocytes, amcâ=âamebocyte, pcâ=âporocytes, spâ=âspicule, mesâ=âmesohyl, picâ=âpinacocytes.</p
Final dereplication by NMR analysis: Sample ACâXâA (âŒ10 ”g) containing the mixture shown in Figure 4 was subjected to NMR determinations at 26°C in CD<sub>3</sub>OD using a high sensitivity 1.7 mm TCI MicroCryoProbe on a 600 MHz Avance Spectrometer (Bruker Biospin).
<p>The annotations shown for the (<b>A</b>) <sup>1</sup>H and (<b>B</b>) <sup>1</sup>Hâ<sup>1</sup>H gCOSY NMR spectra confirm the dereplication assignments proposed in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0100474#pone-0100474-g004" target="_blank">Figure 4</a> for jasplakinolide B (<b>3</b>) (protons coded as âbâ) and jasplakinolide C (<b>2</b>) (protons coded as âcâ), while resonances for jasplakinolde (<b>1</b>) could not be unambiguously observed. Ratios of <b>3</b> to <b>2</b> were estimated to be 60: 40 by peak areas shown in Figure S7 in File S1.</p