Body-plan reorganization in a sponge correlates with microbiome change

Mounting evidence suggests that animals and their associated bacteria interact via intricate molecular mechanisms, and it is hypothesized that disturbances to the microbiome influence animal development. Here, we show that the loss of a key photosymbiont (i.e., bleaching) correlates with a stark body-plan reorganization in the common aquarium cyanosponge Lendenfeldia chondrodes. The morphological changes observed in shaded sponges include the development of a thread-like morphology that contrasts with the flattened, foliose morphology of control specimens. The microanatomy of shaded sponges markedly differed from that of control sponges, with shaded specimens lacking a well-developed cortex and choanosome. Also, the palisade of polyvacuolar gland-cells typical in control specimens was absent in shaded sponges. The morphological changes observed in shaded species are coupled with broad transcriptomic changes and include the modulation of signaling pathways involved in animal morphogenesis and immune response, such as the Wnt, TFG-β, and TLR-ILR pathways. This study provides a genetic, physiological, and morphological assessment of the effect of microbiome changes on sponge post-embryonic development and homeostasis. The correlated response of the sponge host to the collapse of the population of symbiotic cyanobacteria provides evidence for a coupling between the sponge transcriptomic state and the state of its microbiome. This coupling suggests that the ability of animals to interact with their microbiomes and respond to microbiome perturbations has deep evolutionary origins in this group.

Expanded sampling of New Zealand glass sponges (Porifera: Hexactinellida) provides new insights into biodiversity, chemodiversity, and phylogeny of the class

Glass sponges (Hexactinellida) constitute important parts of ecosystems on the deep-sea floor worldwide. However, they are still an understudied group in terms of their diversity and systematics. Here, we report on new specimens collected during RV Sonne expedition SO254 to the New Zealand region, which has recently emerged as a biodiversity hotspot for hexactinellids. Examination of the material revealed several species new to science or so far unknown from this area. While formal taxonomic descriptions of a fraction of these were published earlier, we here briefly report on the morphology of the remaining new species and use the collection to greatly expand the molecular phylogeny of the group as established with ribosomal DNA and cytochrome oxidase subunit I markers. In addition, we provide a chemical fingerprinting analysis on a subset of the specimens to investigate if the metabolome of glass sponges contains phylogenetic signal that could be used to supplement morphological and DNA-based approaches.

The HMA-LMA dichotomy revisited: an electron microscopical survey of 56 sponge species

The dichotomy between high microbial abundance (HMA) and low microbial abundance (LMA) sponges has been long recognized. In the present study, 56 sponge species from three geographic regions (greater Caribbean, Mediterranean, Red Sea) were investigated by transmission electron microscopy for the presence of microorganisms in the mesohyl matrix. Additionally, bacterial enumeration by DAPI-counting was performed on a subset of samples. Of the 56 species investigated, 28 were identified as belonging to the HMA and 28 to the LMA category. The sponge orders Agelasida and Verongida consisted exclusively of HMA species, and the Poecilosclerida were composed only of LMA sponges. Other taxa contained both types of microbial associations (e.g., marine Haplosclerida, Homoscleromorpha, Dictyoceratida), and a clear phylogenetic pattern could not be identified. For a few sponge species, an intermediate microbial load was determined, and the microscopy data did not suffice to reliably determine HMA or LMA status. To experimentally determine the HMA or LMA status of a sponge species, we therefore recommend a combination of transmission electron microscopy and 16S rRNA gene sequence data. This study significantly expands previous reports on microbial abundances in sponge tissues and contributes to a better understanding of the HMA-LMA dichotomy in sponge-microbe symbioses.

Preparation of chitin-silica composites by in vitro silicification of two-dimensional Ianthella basta demosponge chitinous scaffolds under modified Stöber conditions

Chitin is a biopolymer found in cell walls of various fungi and skeletal structures of numerous invertebrates. The occurrence of chitin within calcium- and silica-containing biominerals has inspired development of chitin-based hybrids and composites in vitro with specific physico-chemical and material properties. We show here for the first time that the two-dimensional α-chitin scaffolds isolated from the skeletons of marine demosponge Ianthella basta can be effectively silicified by the two-step method with the use of Stöber silica micro- and nanodispersions under Extreme Biomimetic conditions. The chitin-silica composites obtained at 120 °C were characterized by the presence of spherical SiO2 particles homogeneously distributed over the chitin fibers, which probably follows from the compatibility of Si-OH groups to the hydroxyl groups of chitin. The biocomposites obtained were characterized by various analytical techniques such as energy dispersive spectrometry, scanning electron microscopy, thermogravimetric/differential thermal analyses as well as X-ray photoelectron spectroscopy, Fourier transform infrared and Raman spectroscopy to determine possible interactions between silica and chitin molecule. The results presented proved that the character and course of the in vitro chitin silicification in Stöber dispersions depended considerably on the degree of hydrolysis of the SiO2 precursor.

Chitin-based scaffolds are an integral part of the skeleton of the marine demosponge Ianthella basta

The skeletons of demosponges, such as Ianthella basta, are known to be a composite material containing organic constituents. Here, we show that a filigree chitin-based scaffold is an integral component of the I. basta skeleton. These chitin-based scaffolds can be isolated from the sponge skeletons using an isolation and purification technique based on treatment with alkaline solutions. Solid-state (13)C NMR, Raman, and FT-IR spectroscopies, as well as chitinase digestion, reveal that the isolated material indeed consists of chitin. The morphology of the scaffolds has been determined by light and electron microscopy. It consists of cross-linked chitin fibers approximately 40-100 nm in diameter forming a micro-structured network. The overall shape of this network closely resembles the shape of the integer sponge skeleton. Solid-state (13)C NMR spectroscopy was used to characterize the sponge skeleton on a molecular level. The (13)C NMR signals of the chitin-based scaffolds are relatively broad, indicating a high amount of disordered chitin, possibly in the form of surface-exposed molecules. X-ray diffraction confirms that the scaffolds isolated from I. basta consist of partially disordered and loosely packed chitin with large surfaces. The spectroscopic signature of these chitin-based scaffolds is closer to that of alpha-chitin than beta-chitin.

Aromatic cyclic peroxides and related keto-compounds from the Plakortis sp. component of a sponge consortium

Six unreported aromatic compounds, 1-6, were isolated, along with the known compounds dehydrocurcuphenol and manoalide, from a sample of Plakortis sp., which was the main component of a Pacific sponge consortium. The new molecules were chemically characterized by spectroscopic methods. Compounds 1-4 contain a six-membered cyclic peroxide, whereas 5 and 6 display a terminal methyl ketone. The new metabolites were tested for antifungal and antibacterial properties. Compounds 1 and 4 were weakly active against S. aureus.

Antifouling activity of bromotyrosine-derived sponge metabolites and synthetic analogues

Eighteen brominated sponge-derived metabolites and synthetic analogues were analyzed for antilarval settlement of Balanus improvisus. Only compounds exhibiting oxime substituents including bastadin-3 (4), -4 (1), -9 (2), and -16 (3), hemibastadin-1 (6), aplysamine-2 (5), and psammaplin A (10) turned out to inhibit larval settling at 1 to 10 microM. Analogues of hemibastadin-1 (6) were synthesized and tested for structure activity studies. Debromohemibastadin-1 (8) inhibited settling of B. improvisus, albeit at lower concentrations than hemibastadin-1 (6). Both 6 and 8 also induced cyprid mortality. 5,5'-dibromohemibastadin-1 (7) proved to be nontoxic, but settlement inhibition was observed at 10 microM. Tyrosinyltyramine (9), lacking the oxime function, was not antifouling active and was non-toxic at 100 microM. Hemibastadin-1 (6) and the synthetic products showed no general toxicity when tested against brine shrimp larvae. In contrast to the lipophilic psammaplin A (10), the hydrophilic sulfated psammaplin A derivative (11) showed no antifouling activity even though it contains an oxime group. We therefore hypothesize that the compound needs to cross membranes (probably by diffusion) and that the target for psammaplin A lies intracellularly.

Biotechnological Potential of Marine Sponges and their Associated Bacteria as Producers of New Pharmaceuticals (Part II)

The supply problem

The examples of sponge-derived compounds in advanced stages of clinical trials presented in part I of this article emphasize the potential of sponges as auspicious source for drugs against various human diseases.

However, compared to the vast number of over 4000 compounds isolated from sponges during the last three decades, the number of sponge-derived drugs that have already entered the market is surprisingly small. There are two major reasons for this phenomenon: One is the extremely long time frame involved in the process of drug development. For instance, to develop the famous anticancer drug Taxol® from its initial description in the yew tree to its approval as a commercial pharmaceutical took over 20 years. The presented examples of sponge-derived compounds in clinical trials, this long time frame is by far no exception. Thus, as many interesting compounds were initially reported already in the 1980s and early 1990s, there is hope that within the following years the number of commercially available ”marine drugs” will considerably increase.

Biotechnological Potential of Marine Sponges and their Associated Bacteria as Producers of New Pharmaceuticals (Part I)

Throughout human history natural products have provided the basis for medicinal treatment. About 60 years ago the advent of SCUBA diving techniques granted access to a thitherto untapped source of pharmacologically highly active natural products: the marine environment. In the oceans not plants but sessile animals, particularly sponges, have proven to be the most fruitful organisms in this context. Sponges have evolved a vast arsenal of chemical weapons to defend themselves against various threats from their environment. These molecules remarkably often show potent activities in pharmaceutical assays. Several sponge-derived compounds are already in clinical trials as agents against cancer, microbial infections, inflammation and other diseases. However, in many cases drug development is severely hampered by the limited supply of the respective compounds, as they are often present only in minute amounts in the sponge tissue. Big hope to circumvent this obstacle lies on the supposition that sponge-associated bacteria and not the sponges themselves are in many cases the true producers of the pharmaceutically relevant agents. Once these microorganisms are determined and cultivated outside the sponge tissue, they could be fermented for large-scale compound production. This in future could substantially increase the number of powerful sponge-derived drugs on the market.

Differential effects of staurosporine and its analogues on chemokine release by promyelocytic leukemia cell line NB-4

The protein kinase inhibitor staurosporine elicits multiple responses in various systems. We evaluated nine naturally occurring staurosporine derivatives as modulators of chemokine production by monitoring the secretion of interleukin-8 (IL-8) and monocyte chemotactic protein-1 (MCP-1) in the cell line NB-4. Several staurosporines increased, dose- and time-dependently, the IL-8 and MCP-1 concentration in the cell culture supernatants and three derivatives strongly inhibited proliferation of the NB-4 cells. By comparing the efficiency of these analogues at the same concentration, the lead compound staurosporine (STS-1) was the best inducer of chemokine secretion, whereas 3-hydroxystaurosporine (STS-3) was the most potent growth inhibitor. Besides the staurosporines, also 12-O-tetradecanoyl phorbol acetate (TPA) and tumor necrosis factor-alpha (TNFalpha) strongly increased the IL-8 and MCP-1 secretion of NB-4 cells. Several staurosporine analogues clearly inhibited the TPA-induced but enhanced the TNFalpha-mediated chemokine increase. These effects, namely the increase of chemokines in untreated or TNFalpha-treated cells and the inhibition of chemokine release in TPA-treated cells, cannot be explained by the exclusive inhibition of protein kinase C (PKC). It may indicate that staurosporines are additionally involved in activation of the PKC-triggered chemokine production.

Cytokine gene polymorphisms in atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) and psoriasis are genetically determined inflammatory skin disorders characterized by abnormal cytokine production. From association studies there is evidence that functionally relevant cytokine gene polymorphisms contribute to the genetic basis of psoriasis. Association studies in AD have mostly been limited to polymorphisms of T-helper 2-type cytokines, which dominate in acute AD lesions. Unexpectedly, the results of recent genome scans indicate linkage of AD to psoriasis susceptibility loci. Therefore, AD may also be influenced by genes that modulate cutaneous inflammation independently from atopic mechanisms.

OBJECTIVES

To investigate further the role of cytokine gene polymorphisms in AD.

METHODS

Polymorphisms in the genes encoding tumour necrosis factor-alpha (TNFA-238 G/A, -308 G/A), interleukin (IL)-1beta (IL1B-511 T/C, +3953 T/C), IL-6 (IL6-174 C/G), IL-10 (IL10-1082 A/G) and the IL-1 receptor antagonist (IL1RN intron 2) were investigated in German patients with AD (n = 94) and in healthy nonatopic individuals (n = 214) by polymerase chain reaction-based methods and direct cycle sequencing.

RESULTS

No association was found between AD and any of the polymorphisms analysed. This is in contrast to the recently described association between psoriasis and the TNFA-238 and IL1B-511 polymorphisms.

CONCLUSIONS

Our data indicate that cytokine gene polymorphisms may act as specific markers of inflammatory skin diseases rather than contribute to a general disposition towards cutaneous inflammation.

Eudistomins W and X, two new beta-carbolines from the micronesian tunicate Eudistoma sp

Chemical investigation of the Micronesian ascidian Eudistoma sp. afforded two new eudistomin congeners, which were designated eudistomins W (1) and X (2). The structures of the new compounds were unambiguously established on the basis of NMR spectroscopic ((1)H, (13)C, COSY, (1)H detected direct, and long-range (13)C-(1)H correlations) and mass spectrometric (EI and ESIMS) data. Compound 2 exhibited antibiotic activity toward Bacillus subtilis, Staphyloccocus aureus, and Escherichia coli and was also found to be fungicidal against Candida albicans in an agar diffusion assay. Compound 1 was selectively active against C. albicans but showed no antibacterial activity.

Swinhoeiamide A, a new highly active calyculin derivative from the marine sponge Theonella swinhoei

Analysis of the Papua New Guinean sponge Theonella swinhoei afforded a new calyculinamide-related congener for which we propose the name swinhoeiamide A (1). The structure of the new compound was unambiguously established on the basis of NMR spectroscopic ((1)H, (13)C, COSY, HMBC) and mass spectrometric (FABMS) data. Swinhoeiamide A exhibited insecticidal activity toward neonate larvae of the polyphagous pest insect Spodoptera littoralis when incorporated in an artificial diet offered to the larvae in a chronic feeding bioassay (ED(50) 2.11 ppm, LD(50) 2.98 ppm). Furthermore, it was found to be fungicidal against Candida albicans and Aspergillus fumigatus (MIC 1.2 and 1.0 microg/mL, respectively).

Further new staurosporine derivatives from the ascidian Eudistoma toealensis and its predatory flatworm Pseudoceros sp

Three new indolocarbazole alkaloids, 3-hydroxy-4'-N-methylstaurosporine (3), 3-hydroxy-4'-N-demethylstaurosporine (4), and 3'-demethoxy-3'-hydroxy-4'-N-demethylstaurosporine (5), were isolated from the marine ascidian Eudistoma toealensis and its predatory flatworm Pseudoceros sp. in addition to two known staurosporines. The structures were determined by 1D and 2D homonuclear and 1H-detected heteronuclear NMR spectroscopy and from comparisons with published data. CD measurements for these five staurosporine derivatives, as well as the previously described seven staurosporines, are reported, confirming that all derivatives possess the 2'S,3'R,4'R,6'R configuration.

Anti-proliferative effects of new staurosporine derivatives isolated from a marine ascidian and its predatory flatworm

Nine indolocarbazole alkaloids of the staurosporine type, including three new derivatives, were evaluated for their potential as inhibitors of cell proliferation and macromolecule synthesis. Four derivatives were tested as inhibitors of cell proliferation with twelve human leukemia cell lines and demonstrated powerful antiproliferative activities, with 3-hydroxystaurosporine being the most potent. IC(50) values were determined using the cell line MONO-MAC-6 and with an IC(50) of 13 ng/ml, 3-hydroxystaurosporine turned out to be one of the most active staurosporine-type inhibitors described so far. All derivatives, except 3-hydroxy-3'-demethoxy-3'-hydroxystaurosporine and 4'-N-methylstaurosporine very strongly reduced RNA and DNA synthesis with 3-hydroxystaurosporine again being the strongest inhibitor. Analysis of structure-activity relationships demonstrated that hydroxylation of staurosporine at position 3 of the indolocarbazole moiety caused an increase in anti-proliferative activity, while hydroxylation at carbon 11 resulted in a decrease in activity. Our results suggest that not only the presence or absence of hydrophilic substitutions, but also the position of the alteration within the molecule, is important in the antiproliferative properties of the various staurosporine analogues.

Cowpox virus in a 12-year-old boy: rapid identification by an orthopoxvirus-specific polymerase chain reaction

Although smallpox was eradicated 20 years ago, other members of the genus Orthopoxvirus (OPV), such as cowpox virus (CPXV) or monkeypox virus, are still a threat to humans. Because human CPXV infection is rare, it is seldom suspected on clinical grounds only. We report a boy who presented with two necrotic ulcers with surrounding erythema. Infection with OPV was suspected, as antibiotic treatment had not produced improvement and smears were negative for anthrax. An OPV was isolated and an OPV-specific polymerase chain reaction combined with a subsequent restriction enzyme fragment length polymorphism assay confirmed infection by CPXV. Although the patient's cat had had no skin lesions, OPV-specific antibodies were found at a titre of 1 : 8 in a plaque reduction assay, suggesting that the cat had transmitted the virus to the boy.

Topography of sham and real puffing examined using a paced smoking regimen

Topographical patterns of normal puffing on a cigarette may be reflected in the topographical patterns of sham puffing (Morris & Gale, 1994). To test further the possibility of measuring behavior associated with cigarette smoke self-administration without actual smoke intake, we compared sham and real puffing using a paced smoking regimen under different levels of smoke deprivation. Cigarette smokers were instructed to draw and inhale six times on their unlit and then subsequently on their lit cigarette. Intensity, maximum, area and duration of puffs were lower for sham as opposed to real puffing; however, sham and real puffing showed parallel changes in response to deprivation, and significant positive correlations were found between the two puffing conditions for puff intensity, maximum and area. Therefore, we confirmed a similarity of real puffing with puffing under placebo conditions. Discussed was smoking as an automatic motor behavior.

Staurosporine derivatives from the ascidian eudistoma toealensis and its predatory flatworm pseudoceros sp

Two new indolocarbazole alkaloids, 3-hydroxy-3'-demethoxy-3'-hydroxystaurosporine (5) and 11-hydroxy-4'-N-demethylstaurosporine (6), were isolated from the marine ascidian Eudistoma toealensis and its predator, the marine flatworm Pseudoceros sp. In addition, five known derivatives were isolated in their protonated states, which caused the pyran-ring system to adopt a boat conformation. The structures were determined by 1D and 2D homonuclear and (1)H-detected heteronuclear NMR spectroscopy and from comparisons with published data. The heteronuclear correlations were necessary to establish reliable data for the structure elucidation.

Bioactive pyridoacridine alkaloids from the micronesian sponge Oceanapia sp

The Micronesian sponge Oceanapia sp. afforded three pyridoacridine alkaloids: the known compounds kuanoniamine C (1) and kuanoniamine D (2), as well as the new N-deacyl derivative (3) of the kuanoniamines. Compounds 1 and 2 exhibited insecticidal activity toward neonate larvae of the polyphagous pest insect Spodoptera littoralis (LC50 of 156 and 59 ppm, respectively), when incorporated into artificial diet. Both compounds also showed toxicity in the brine shrimp lethality test with a LC50 of 37 micrograms/mL (compound 1) and 19 micrograms/mL (compound 2), respectively. The N-deacyl derivative did not show any remarkable effect in both bioassays. Cytotoxcity of the alkaloids was studied in vitro, using two human cell lines. The new derivative (3) appeared to be active in the same range of concentrations as kuanoniamine C (1) and D (2). The IC50 of 3 was 1.2 micrograms/mL toward HeLa cells and 2.0 micrograms/mL toward MONO-MAC 6 cells. In receptor binding assays compound 2 showed affinity to A1- and A2A-adenosine receptors with Ki values of 2.94 and 13.7 microM, respectively. Compound 1 was less active than compound 2, whereas compound 3 showed no affinity toward adenosine receptors. In addition, compounds 1-3 exhibited moderate affinity to benzodiazepine binding sites of GABAA receptors.

Esterase-16 (es-16): characterization, polymorphism, and linkage to chromosome 3 of a kidney esterase locus of the house mouse

A polymorphism for an isozyme of a presumed arylesterase, esterase-16 (EC 3.1.1.2), has been detected in kidney, heart, and spleen of the house mouse, Mus musculus, by means of isoelectric focusing and by disc electrophoresis. Three phenotypes can be distinquished: the ES-16A phenotype (IEP 5.9) was found in C57BL/10Sn and many other laboratory inbred strains; the ES-16B phenotype (IEP 6.1) was found in M. m. molossinus; and the ES-16C phenotype (IEP 5.9; very weak activity) was found in Peru-Coppock. Esterase-16 is strongly inhibited by 10(-3) M p-chloromercuribenzoate, but not by 2. 10(-4) M bis-p-nitrophenyl phosphate or by 10(-3) M Diamox. It stains well with indoxyl acetate and other indigogenic substrates but only weakly with alpha-naphthyl acetate. Esterase-16 is completely insoluble in water. It is apparently governed by a structural gene locus, Es-16, with three alleles, Es-16a, Es-16b, and ES-16c, respectively. Es-16 is closely linked to Car-1 and Car-2 on chromosome 3 Typing of 94 animals of the backcross (C57BL/10Sn x M. m. mol.) F1 x M. m. mol. revealed a recombination frequency of 8.51 /+- 2.9%.