Axinella Sp Research Articles

Antibacterial activities of bacteria associated with marine sponges of Axinella sp. on Carbapenem-Resistant Acinetobacter Baumannii (CRAB)

Carbapenem-resistant Acinetobacter baumannii (CRAB) is a gram-negative bacillus that commonly causes nosocomial infection found in Indonesia. CRAB infection caused by Acinetobacter baumannii that is resistant to Carbapenem. Resistance occurred because bacteria that cause infections easily treated with antibiotics become difficult to treat due to the uncontrolled use of antibiotics. A. baumannii has been resistant against the carbapenem class of antibiotics; and therefore, antibiotics are required to be obtained from natural ingredients with optimal working power, such as from the marine sponges of Axinella sp. The purpose of this study was to determine the antibacterial activities of bacteria associated with marine sponges of Axinella sp. against CRAB. Bacteria associated with Axinella sp. were isolated by differential dilution and cultures on Zobell 2216E media. An antibacterial activity test was performed using the overlay method. The antibacterial activity test was carried out to determine the presence of inhibition zones. The test results showed the bacteria associated with a marine sponge of Axinella sp strain 3 KD had antibacterial activity against CRAB growth with the formation of an inhibition zone of 16 mm. The results of the catalase test and oxidase test depicted that the isolates belong to the family of Staphylococcaceae. Isolates bacteria associated with a marine sponge of Axinella sp. were potential antibacterial agents against CRAB growth.

Axinellasins A-D, Immunosuppressive Cycloheptapeptide Diastereomers, Discovered via a Precursor Ion Scanning-Supercritical Fluid Chromatography Strategy from the Marine Sponge Axinella species.

The precursor ion scanning-supercritical fluid chromatography (PI-SFC) method was applied to explore new methionine sulfoxide-containing cycloheptapeptides, axinellasins A-D (1-4), from the marine sponge Axinella sp. Their structures, including absolute configurations, were elucidated by detailed spectroscopic analyses and X-ray crystallography. The total synthesis of 4 was completed via an Fmoc solid/solution-phase synthesis. Compounds 1-4 exhibited immunosuppressive effects via inhibition of T and B cell proliferation, and 1 and 4 showed better inhibitory activities than their corresponding diastereomers.

Cultivation of fractionated cells from a bioactive-alkaloid-bearing marine sponge Axinella sp.

Sponges are among the most primitive multicellular organisms and well-known as a major source of marine natural products. Cultivation of sponge cells has long been an attractive topic due to the prominent evolutionary and cytological significance of sponges and as a potential approach to supply sponge-derived compounds. Sponge cell culture is carried out through culturing organized cell aggregates called 'primmorphs.' Most research culturing sponge cells has used unfractionated cells to develop primmorphs. In the current study, a tropical marine sponge Axinella sp., which contains the bioactive alkaloids, debromohymenialdisine (DBH), and hymenialdisine (HD), was used to obtain fractionated cells and the corresponding primmorphs. These alkaloids, DBH and HD, reportedly show pharmacological activities for treating osteoarthritis and Alzheimer's disease. Three different cell fractions were obtained, including enriched spherulous cells, large mesohyl cells, and small epithelial cells. These cell fractions were cultivated separately, forming aggregates that later developed into different kinds of primmorphs. The three kinds of primmorphs obtained were compared as regards to appearance, morphogenesis, and cellular composition. Additionally, the amount of alkaloid in the primmorphs-culture system was examined over a 30-d culturing period. During the culturing of enriched spherulous cells and developed primmorphs, the total amount of alkaloid declined notably. In addition, the speculation of alkaloid secretion and some phenomena thatoccurred during cell culturing are discussed.

Recifin A, Initial Example of the Tyr-Lock Peptide Structural Family, Is a Selective Allosteric Inhibitor of Tyrosyl-DNA Phosphodiesterase I.

Tyrosyl-DNA phosphodiesterase 1 (TDP1) is a molecular target for the sensitization of cancer cells to the FDA-approved topoisomerase inhibitors topotecan and irinotecan. High-throughput screening of natural product extract and fraction libraries for inhibitors of TDP1 activity resulted in the discovery of a new class of knotted cyclic peptides from the marine sponge Axinella sp. Bioassay-guided fractionation of the source extract resulted in the isolation of the active component which was determined to be an unprecedented 42-residue cysteine-rich peptide named recifin A. The native NMR structure revealed a novel fold comprising a four strand antiparallel β-sheet and two helical turns stabilized by a complex disulfide bond network that creates an embedded ring around one of the strands. The resulting structure, which we have termed the Tyr-lock peptide family, is stabilized by a tyrosine residue locked into three-dimensional space. Recifin A inhibited the cleavage of phosphodiester bonds by TDP1 in a FRET assay with an IC50 of 190 nM. Enzyme kinetics studies revealed that recifin A can specifically modulate the enzymatic activity of full-length TDP1 while not affecting the activity of a truncated catalytic domain of TDP1 lacking the N-terminal regulatory domain (Δ1-147), suggesting an allosteric binding site for recifin A on the regulatory domain of TDP1. Recifin A represents both the first of a unique structural class of knotted disulfide-rich peptides and defines a previously unseen mechanism of TDP1 inhibition that could be productively exploited for potential anticancer applications.

Potential foraging and aggregation zones of the Hawksbill Sea Turtle Eretmochelys imbricata (Testudines: Cheloniidae), near Marino Ballena National Park, Costa Rica

Groups of hawksbill sea turtles have been observed over the years, close to the coast of the Marino Ballena National Park. For this reason, in February 2015, we monitored its coast to identify aggregation sites. Turtle size estimates, and identification, were done by direct observation by the divers and from the boat. From February to December 2015, fourteen monitor records per sampling point were done and 41 turtles were recorded. They were 30cm - 80cm long and 59% of the individuals aggregated in one sample point. Five genera of sponges were registered as potential food: Haliclona sp, Spirastrella sp, Mycale sp, Aplyscina sp and Axinella sp and one tunicate, Rhopalaea birkelandi. The E. imbricata population was mainly composed of juveniles, and the turtles were found in zones where they have not been previously reported.

Axinellin A and B: Two New Pyrrolactam Alkaloids from Axinella sp.

Two new pyrrolactam alkaloids, axinelline A (1) and B (2), were isolated from the n-BuOH extract of marine sponge Axinella sp. The structures of these compounds were elucidated on the basis of spectroscopic methods (HR-ESI-MS, 1D and 2D NMR).

Symbiotic Fungus of Marine Sponge Axinella sp. Producing Antibacterial Agent

The emerging of multidrug resistance pathogenic bacteria cause the treatment of the diseaseshave become ineffective. There for, invention of a new drug with novel mode of action is an essential for curing the disease caused by an MDR pathogen. Marine fungi is prolific source of bioactive compound that has not been well explored. This study aim to obtain the marine sponges-associated fungus that producing anti-MDR bacteria substaces. We collected the sponge from Riung water, NTT, Indonesia. The fungus was isolated with affixed method, followed with purification with streak method. The overlay and disk diffusion agar methods were applied for bioactivity test for the isolate and the extract, respectively. Molecular analysis was employed for identification of the isolate. The sponge was identified based on morphological and spicular analysis. The ovelay test showed that the isolate KN15-3 active against the MDR Staphylococcus aureus and Eschericia coli. The extract of the cultured KN15-3 was also inhibited the S. aureus and E. coli with inhibition zone 2.95 mm and 4.13 mm, respectively. Based on the molecular analysis, the fungus was identified as Aspergillus sydowii. While the sponge was identified as Axinella sp.

English

English

Antifouling activities of hymenialdisine and debromohymenialdisine from the sponge Axinella sp.

Being physically unprotected sessile organisms, marine sponges are thought to protect themselves from surface fouling through the use of antifouling secondary metabolites. In this study, the sponge Axinella sp. was extracted with methanol and then partitioned between organic solvents and water. Two main compounds, hymenialdisine (HD) and debromohymenialdisine (DBH), were isolated from the n-BuOH layer using Sephadex LH-20 and C-18 column chromatography. The antifouling activity of HD and DBH were evaluated using the test of byssus thread production with the green mussel Perna viridis, and the settlement assays with the bryozoan Bugula neritina larvae and the green alga Ulva prolifera spores. Both HD and DBH were found to exhibit significant antifouling activities against P. viridis (EC50 values of 31.77 and 138.18 μg ml−1, respectively), B. neritina (EC50 values of 3.43 and 8.17 μg ml−1, respectively) and U. prolifera (EC50 values of 8.31 and 0.67 μg ml−1, respectively). Our results suggested that HD and DBH may play a role in chemical defense against fouling in Axinella sp.

Marking spherulous cell in marine sponge Axinella sp. using a 3,3′- diaminobenzidine (DAB) staining method

Debromohymenialdisine(DBH) and hymenialdisine(HD) are two bioactive alkaloids which has been isolated from marine sponge Axinella sp.living in the South China Sea,and these two alkaloids are located particularly in spherulous cells in Axinella sp..Establishment of a specific marker for this type of cells by cytochemical staining can provide an indication method for cell differentiation,and can be applied in the metabolism regulation in in vitro cell culture.The 3,3′-diaminobenzidine(DAB) staining is commonly used to detect peroxidase activity.In this study,sponge cells were fractionated and stained by DAB.A distinguishing feature of dark brown granules in cytoplasm was observed in spherulous cells.Native-PAGE was carried out with protein extracts from fresh tissue and different cell fractions of marine sponge to examine the peroxidase responsible for DAB staining.By transmission electron microscope(TEM),two kinds of inclusions were found inside the spherulous cells,the larger ones of which showed consistency in dimen-sion and amount with the positive stained granules under light microscopy.In addition,this staining method for spheru-lous cell identification was also applied in in vitro cell culture(primmorph culture).The proportion of both granularly positive-stained cells and the spherulous cells synchronously varied during a 20-day culture period,and the ratio of positive-stained spherulous cells was kept above 93%.The above results suggested that the cytochemical method of DAB staining was reliable and could be applied in both fresh-tissue dissociation and in vitro cell culture,with the dis-tinctive characteristic of positive stained granules in cytoplasm marking spherulous cells in sponge Axinella sp..

A new taurine derivative from South China Sea marine sponge Axinella sp.

A new (1) and two known (2 and 3) acylated taurine derivatives were isolated from the South China Sea marine sponge Axinella sp. The structures of the compounds were determined on the basis of spectral analysis. Compounds 1–3 did not inhibit the growth of hepatoma carcinoma cell (HepG2), lung carcinoma cell (A549), human breast carcinoma (MCF-7), no-small cell lung cancer (NCI-H460) and human nasopharyngeal carcinoma cell lines.

A search for kinase inhibitors and antibacterial agents: bromopyrrolo-2-aminoimidazoles from a deep-water Great Australian Bight sponge, Axinella sp.

Biological screening of a deep-water Great Australian Bight marine sponge, Axinella sp., detected inhibition against the neurodegenerative disease kinase targets CDK5/p25, CK1δ, and GSK3β, as well as significant levels of antibacterial activity. Chemical fractionation returned 18 secondary metabolites identified by detailed spectroscopic analysis as three new bromopyrrolo-2-aminoimidazoles, 14-O-sulfate massadine (1), 14-O-methyl massadine (2), and 3-O-methyl massadine chloride (3), together with the known metabolites massadine chloride (4), massadine (5), stylissadine B (6), axinellamines A–C (7–9), hymenin (10), stevensine (also known as odiline) (11), tauroacidin A (12), hymenidin (13), taurodispacamide A (14), oroidin (15), debromohymenialdisine (16), hymenialdisine (17), and aldisin (18). Armed with this focused natural product chemical diversity library, we re-established that 16 and 17 were nM kinase inhibitors, and determined that 3, 6, and 12–15 were sub μM antibacterials.

Cellular Localization of Debromohymenialdisine and Hymenialdisine in the Marine Sponge Axinella sp. Using a Newly Developed Cell Purification Protocol

Sponges (Porifera), as the best known source of bioactive marine natural products in metazoans, play a significant role in marine drug discovery and development. As sessile filter-feeding animals, a considerable portion of the sponge biomass can be made of endosymbiotic and associated microorganisms. Understanding the cellular origin of targeted bioactive compounds from sponges is therefore important not only for providing chemotaxonomic information but also for defining the bioactive production strategy in terms of sponge aquaculture, cell culture, or fermentation of associated bacteria. The two alkaloids debromohymenialdisine (DBH) and hymenialdisine (HD), which are cyclin-dependent kinase inhibitors with pharmacological activities for treating osteoarthritis and Alzheimer's disease, have been isolated from the sponge Axinella sp. In this study, the cellular localization of these two alkaloids was determined through the quantification of these alkaloids in different cell fractions by high-performance liquid chromatography (HPLC). First, using a differential centrifugation method, the dissociated cells were separated into different groups according to their sizes. The two bioactive alkaloids were mainly found in sponge cells obtained from low-speed centrifugation. Further cell purifications were accomplished by a newly developed multi-step protocol. Four enriched cell fractions (C1, C2, C3, and C4) were obtained and subjected to light and transmission electron microscopy, cytochemical staining, and HPLC quantification. Compared to the low concentrations in other cell fractions, DBH and HD accounted for 10.9% and 6.1%, respectively, of dry weight in the C1 fraction. Using the morphological characteristics and cytochemical staining results, cells in the C1 fraction were speculated to be spherulous cells. This result shows that DBH and HD in Axinella sp. are located in sponge cells and mostly stored in spherulous cells.

A type of characteristic peroxisome in the spherulous cells of the marine sponge Axinella sp.

A type of characteristic peroxisome in the spherulous cells of the marine sponge Axinella sp.

Steroids and alkaloids from the South China Sea sponge Axinella sp.

A new steroid 24β-methylcholasta-1,8,14,22,25-penten-3-one-5α-ol (1) and a new alkaloid 1-(1H-indol-3-yl)-2,3-dihydroxy-5-methyl-hexane (2), together with four known compounds, were isolated from the EtOH extract of the South China Sea sponge Axinella sp. The structures of 1 and 2 were determined on the basis of extensive spectroscopic analysis, including 1D and 2D NMR spectral data.

Isolation and Difference in Anti-Staphylococcus aureus Bioactivity of Curvularin Derivates from Fungus Eupenicillium sp.

With the anti-microbial and anti-tumor composite screening model, bioassay-guided fractionation led to the isolation of two structurally related bioactive compounds, curvularin and alphabeta-dehydrocurvularin, from ethyl acetate extract of Eupenicillium sp. associated with marine sponge Axinella sp. Further study on the structure-activity relationship demonstrated that both compounds exhibited differences in bioactive profiles which are highly associated with their minor structural differences. Both curvularin and alphabeta-dehydrocurvularin have similar level of anti-fungal and anti-tumorous activity, while alphabeta-dehydrocurvularin is active against Staphylococcus aureus with a minimal inhibitory concentration of 375 microg/ml but curvularin does not. No detectable activity against Gram-negative bacteria such as Escherichia coli and Pseudomonas aeruginosa exists for both compounds. It is suggested that the partial planar backbone structure, due to the conjugation of pi electrons in the presence of a 3,4-double bond and the carbonyl group at position C-2 in alphabeta-dehydrocurvularin, acts as a key factor for the inhibition of S. aureus, a Gram-positive low G + C bacteria that are often the hospital-acquired and/or community-acquired pathogen.

A novel D-ring unsaturated A-nor sterol from the Indonesian sponge, Axinella carteri Dendy

Investigation of the freeze-dried dichloromethane: isopropanol extract of the sponge Axinella carteri Dendy, 1889 (Demospongiae: Halichondrida: Axinellidae), collected from Derawan Island, Indonesia, has led to the isolation of a new A-nor sterol with rare D-ring unsaturation, 3β-(hydroxymethyl)-A-nor-5α-cholest-14-en-16-one (1). While the efficacy of the new compound is unknown, moderate cytotoxicity was observed in the fraction from which it was purified. A more polar portion of the extract afforded the known alkaloid dibromoisophakellin (2), previously isolated from an Axinella sp. The purification of the compounds was achieved on silica gel and Sephadex LH-20 supports and the identity of the compounds was established with the aid of 1D and 2D NMR spectroscopic experiments.

Cellular localization and quantification of bioactive alkaloids hymenialdisine and debromohymenialdisine in marine sponge Axinella sp.

Cellular localization and quantification of bioactive alkaloids hymenialdisine and debromohymenialdisine in marine sponge Axinella sp.

Potential inhibitors against Sclerotinia sclerotiorum, produced by the fungus Myrothecium sp. associated with the marine sponge Axinella sp.

Sclerotinia sclerotiorum is a worldwide ascomycete fungal plant pathogen, which causes enormous yield losses on major economic crops such as crucifers, grain legumes and several other plant families. The objective of this research was to isolate and characterise some bioactive products from cultures of fungi associated with the marine sponge Axinella sp. In total, nine fungal isolates were obtained from the marine sponge Axinella sp. collected from the South China Sea. A group of test strains, including two G+ strains (Bacillus subtilis and Staphylococcus aureus), two G− strains (Escherichia coli and Pseudomonas aeruginosa) and three fungi including two plant pathogenic fungi Sclerotinia sclerotiorum and Magnaporthe grisea and Saccharomyces cerevisiae, were employed as the indicator organisms for bioactivity screening. Using antagonistic tests and bioactive screening of the ethyl acetate (EtOAc) extracts of the corresponding cultures, fungal isolate JS9 showed the stronger efficacy against the test indicator strains, especially the indicator fungal pathogens. Isolate JS9 was further identified as Myrothecium sp. by a combination of morphological features and 18S rDNA BLAST on GenBank. Two macrocyclic trichothecenes, roridin A (compound 1) and roridin D (compound 2) were purified by tracking the activity of the EtOAc extract fractions and characterised with spectral analyses including MS, 1H-NMR, 13C-NMR and disortionless enhancement by polarization transfer (DEPT). In vitro antifungal tests showed that the two macrocyclic trichothecenes were bioactive against S. cerevisiae, M. grisea and S. sclerotiorum with minimal inhibitory concentrations of 31.25, 125 and 31.25 μg ml−1 for roridin A, and 62.5, 250 and 31.25 μg ml−1 for roridin D, respectively. The present investigation demonstrated that two antifungal trichothecenes including roridin A and roridin D produced by the fungus Myrothecium sp. isolated from the marine sponge Axinella sp. could be potential inhibitors against the plant pathogen S. sclerotiorum.

A new cycloamphilectene metabolite from the Vanuatu sponge Axinella sp.

A new diterpene, N-formyl-7-amino-11-cycloamphilectene (1), was isolated from the apolar extract of the Vanuatu sponge Axinella sp. The structure and relative stereochemistry were established by spectroscopic and single-crystal X-ray studies.