Cyclopoid copepods (Lichomolgidae) associated with the coral genus Favites in the Moluccas

Three new species of Lichomolgidae, Cerioxynus moluccensis, Cerioxynus bandensis , and Rakotoa ceramensis , are described from the scleractinian corals Favites pentagona (Esper) and Favites virens (Dana) in Ceram and Banda.     

Two siphonostomatoid copepods (Coralliomyzontidae) associated with the ahermatypic coral Tubastraea in the Moluccas

Two siphonostomatoid copepods (Coralliomyzontidae) are associatedwith the ahermatypic coral Tubastraea micracantha at Banda inthe Moluccas. Cholomyzon brevisetigerum, new species, hasunusually short setae on the caudal rami. Corallimyzonlatitergum, new species, has an enlarged, posteriorly slightlytrilobate tergum on the third metasomal somite and lacksleg 4.     

Metabolites from a marine bacterium Pseudomonas/Alteromonas, associated with the sponge Dysidea fragilis

The lipophylic extract from a Black Sea bacterium, associated with the sponge Dysidea fragilis, was investigated. Saturated hydrocarbons and fatty acids of the lipids were identified. The concentrations of the polycyclic compounds appeared to be negligible. The main components appeared to be phosphatidyl ethanolamine, followed by phosphatidyl serine. The first was investigated by FAB mass spectrometry and a series of molecular species partially identified.     

Cellular origin of chlorinated diketopiperazines in the dictyoceratid sponge Dysidea herbacea (Keller)

The tropical marine sponge Dysidea herbacea (Keller) contains the filamentous unicellular cyanobacterium Oscillatoria spongeliae (Schulze) Hauck as an endosymbiont, plus numerous bacteria, both intracellular and extracellular. Archaeocytes and choanocytes are the major sponge cell types present. Density gradient centrifugation of glutaraldehyde-fixed cells with Percoll as the support medium has been used to separate the cyanobacterial symbiont from the sponge cells on the basis of their differing densities. The protocol also has the advantage of separating broken from intact cells of O. spongeliae. The lighter cell preparations contain archaeocytes and choanocytes together with damaged cyanobacterial cells, whereas heavier cell preparations contain intact cyanobacterial cells, with less than 1% contamination by sponge cells. Gas chromatography/mass spectrometry analysis has revealed that the terpene spirodysin is concentrated in preparations containing archaeocytes and choanocytes, whereas nuclear magnetic resonance analysis of the symbiont cell preparations has shown that they usually contain the chlorinated diketopiperazines, dihydrodysamide C and didechlorodihydrodysamide C, which are the characteristic metabolites of the sponge/symbiont association. However, one symbiont preparation, partitioned by a second Percoll gradient, has been found to be devoid of chlorinated diketopiperazines. The capability to synthesize secondary metabolites may depend on the physiological state of the symbiont; alternatively, there may be two closely related cyanobacterial strains within the sponge tissue.     

Two new species of Copepoda associated with the basket star Astroboa nuda (Ophiuroidea) in the Moluccas

Doridicola connexus sp.n. (Poeclostomatoida, Lichomolgidae) and Collocherides singularis sp.n. (Siphonostomatoida, Asterocheridae) are described from specimens found on the ophiuroid Astroboa nuda in the Moluccas. D. connexus may be recognized by the small discoidal free segment of leg 5 in the female. C. singularis is characterized by having only one seta on the second segment of the endopod of legs 1–3 and by the rounded inner lobe on the proximal segment of leg 5.     

Bacteria associated with an encrusting sponge (Terpios hoshinota) and the corals partially covered by the sponge

Terpios hoshinota, a dark encrusting sponge, is known to be a competitor for space in coral reef environments, and facilitates the death of corals. Although numerous cyanobacteria have been detected in the sponge, little is known of the sponge-associated bacterial community. This study examined the sponge-associated bacterial community and the difference between the bacterial communities in the sponge and the coral partially covered by the sponge by analysis of 16S rRNA gene sequences of samples isolated from the sponge covering the corals Favia complanata, Isopora palifera, Millepora sp., Montipora efflorescens and Porites lutea. The sponge-associated bacterial community was mainly (61-98%) composed of cyanobacteria, with approximately 15% of these alphaproteobacteria and gammaproteobacteria, although the proportions varied in different sponge samples. The dominant cyanobacteria group was an isolated group closely related to Prochloron sp. The comparison of the bacterial communities isolated from sponge-free and the sponge-covered P. lutea showed that covering by the sponge caused changes in the coral-associated bacterial communities, with the presence of bacteria similar to those detected in black-band disease, suggesting the sponge might benefit from the presence of bacteria associated with unhealthy coral, particularly in the parts of the coral closest to the margin of the sponge.     

Avarol, a cytostatically active compound from the marine sponge Dysidea avara

A main metabolic product of the sponge Dysidea avara was isolated and purified and subsequently identified as avarol by applying a series of analytical techniques, e.g. [13C]NMR, [1H]NMR and i.r. spectroscopy. This sesquiterpenoid hydroquinone was found to possess strong cytostatic activity. Using the L5178y mouse lymphoma cell system in vitro (roller tube assays) avarol reduced cell growth to 50% at a concentration of 0.9 microM. Avarol treated cells did not show "unbalanced growth". Avarol interfered with mitotic processes, preventing telophase formation. Incorporation studies with precursors for DNA, RNA, protein and glycoprotein syntheses revealed increased incorporation rates in response to avarol treatment. From these results and further autoradiographical experiments it is suggested that inhibition of cell growth is due to changes of the intracellular pools and/or alterations of the permeability properties of the cell membrane for the precursors. Avarol diacetate caused the same cytostatic effect as avarol.     

Semi-synthesis and bio-evaluation of polybrominated diphenyl ethers from the sponge Dysidea herbacea

The sponge Dysidea herbacea was collected from the Mandapam Coast, Tamilnadu, India. Isolated gram quantities of hydroxylated polybrominated diphenyl ether (HO-PBDE) and semi-synthesized a series of new PBDEs derivatives and tested them for antibacterial and cytotoxic activities.     

Asterocheres flustrae n. sp. (Copepoda: Siphonostomatoida: Asterocheridae) associated with Flustra foliacea L. (Bryozoa) from the White Sea

Asterocheres flustrae n. sp. is described from Flustra foliacea L. (Bryozoa) found in the Kandalaksha Bay of the White Sea. This is the first siphonostomatoid copepod to be reported in association with a bryozoan. Distinctive features of the new species are: (1) a female with 21- and male with 18-segmented antennules; (2) five setae on the inner lobe of the maxillule with one much reduced; (3) an aesthetasc on the syncoxa of the maxilla; (4) a 6-segmented maxilliped with a distal claw; and (5) the armature of endopodal segments 2, 1, 1 and 1. Sexual dimorphism was observed not only on the antennules, but also for maxilliped and legs 1–6. By using SEM some new fine structures were revealed, including: one seta on each of antennulary segments 1 to 4, 6 and 8 with a nipple-like tip and an apical pore surrounded at its base by a circlet of cuticular denticles; a rostral region having a circular area ornamented with minute cuticular protuberances; and the labrum ornamented with fine hair-like setules on either side of its apex.     

Differences between the floras of the North and South Moluccas (Indonesia)

The north and south Moluccas (Indonesia) have very different geotectonic origins and, due to that, a difference in flora is to be expected. The north Moluccas moved westwards along the north coast of New Guinea to their present position, the south Moluccas moved north from Australia. On the other hand, a comparable climate in both areas and (partial) submergence during tectonic movement may have equalized both floras. Collection data from Naturalis Biodiversity Center on 1559 species in 121 families treated in Flora Malesiana were collected for the Moluccas, Sulawesi, and Western New Guinea (latitudes 9.2°S and 5.6°N and longitudes 118.8°E and 141°E) and georeferenced. Species Distribution Models (SDMs) were made, based on least correlated climate and edaphic variables, using only those species that were present in 5 or more grid cells of 5-arc minutes and models were tested for deviation from random. Both areas differ significantly and share only 50%-65% of their species. The 348 significant SDMs differ much less, though still significantly, sharing 91% of the species. Despite strong climatic and edaphic similarities between the North and South Moluccas, they differ greatly in species composition, which is in support of geotectonic reconstructions. The differences between the North and South Moluccas suggest that the continuous dispersal barriers and tectonic backgrounds have influenced their current flora.     

Cyclopoid copepods associated with marine invertebrates in Mauritius

Three species of Sabelliphilidae and four species of Lichomolgidae are reported as associates of scleractinian corals, nudibranchs, polychaetes, asteroids, and holothurians in Mauritius. A sabelliphilid from the polychaete Sabellastarte magnifica represents a new genus and species. Two previously described lichomolgids are recorded from new hosts. Species ranges are extended from Madagascar and New Caledonia to Mauritius.     

Characterization of urethanase from Micrococcus species associated with the marine sponge (Spirasfrella species)

B.R. Mohapatra and M. Bapuji. 1997. Eighty per cent of the urethanase activity of Micrococcus sp. isolated from the marine sponge Spirastrella sp. was cell associated. The urethanase had optimal activity at pH 5.0 and 45 °C. The activation and deactivation energies of the partially purified enzyme, calculated from an Arrhenius plot, were 9.31 and 34.01 kcal mol⁻¹, respectively. The enzyme was not affected by EDTA and the major cations of sea water, such as Ca²⁺, Mg²⁺ and Na⁺. The enzyme was resistant to 20% (v/v) ethanol and may be practically applicable in the removal of urethane from alcoholic beverages.     

Inhibition of mitosis by avarol, a natural product isolated from the sponge Dysidea avara

Avarol, a sesquiterpenoid hydroquinone, is a cytostatic agent, isolated from the sponge Dysidea avara. Autoradiographic studies show that in vivo (L5178y mouse lymphoma cells) avarol changes the labelling index in favour of the fraction of unlabelled cells (from 1.24 to 1.04). At concentrations below the 50% inhibition dose, the mitotic index increases from 6.5 +/- 0.5 to 10.4 +/- 0.8; at higher concentrations the formation of mitotic figures is almost completely suppressed. In vitro studies applying the methods of viscosimetry and electron microscopy demonstrate that avarol inhibits assembly of brain microtubule protein at an at least stoichiometric concentration ratio. Moreover, evidence is presented that the new antimitotic agent avarol inhibits protofilament elongation rather than lateral association of tubulin during protofilament formation. The results suggest that avarol interferes with polymerization of tubulin both in interphase and during mitosis.     

Polybrominated diphenyl ethers from a sponge of the Dysidea genus that inhibit Tie2 kinase

Tie2 kinase, an enzyme that supports angiogenesis essential for tumor growth and survival, was selected as a target in a search for naturally occurring inhibitors of potential utility for antitumor therapy. Two polybrominated diphenyl ethers, 3,5-dibromo-2-(2',4'-dibromophenoxy)phenol (1) and 4,6-dibromo-2-(2',4'-dibromophenoxy)phenol (2) were isolated from an extract prepared from Dysidea sp. after bioassay-guided fractionation.     

Diversity and community structure of harpacticoid copepods associated with cold-water coral substrates in the Porcupine Seabight (North-East Atlantic)

The influence of microhabitat type on the diversity and community structure of the harpacticoid copepod fauna associated with a cold-water coral degradation zone was investigated in the Porcupine Seabight (North-East Atlantic). Three substrate types were distinguished: dead fragments of the cold-water coral Lophelia pertusa, skeletons of the glass sponge Aphrocallistes bocagei and the underlying sediment. At the family level, it appears that coral fragments and underlying sediment do not harbour distinctly different assemblages, with Ectinosomatidae, Ameiridae, Pseudotachidiidae, Argestidae and Miraciidae as most abundant. Conclusions on assemblage structure and diversity of the sponge skeletons are limited as only two samples were available. Similarity analysis at species level showed a strong variation in the sediment samples, which did not harbour a distinctly different assemblage in opposition to the coral and sponge samples. Several factors (sediment infill on the hard substrates, mobility of the copepods, limited sample sizes) are proposed to explain this apparent lack of a distinct difference between the microhabitats. Coral fragments and sediment were both characterised by high species diversity and low species dominance, which might indicate that copepod diversity is not substantially influenced by hydrodynamical stress. The additive partitioning of species diversity showed that by adding locations species richness was greatly enhanced. The harpacticoid community in the cold-water coral degradation zone is highly diverse and includes 157 species, 62 genera and 19 families. Information from neighbouring soft-bottom regions is necessary to assess whether total species diversity is increased by the presence of these complex habitat-providing substrates.     

Inhibition of Candida albicans isocitrate lyase activity by sesterterpene sulfates from the tropical sponge Dysidea sp

Seven sesterterpene sulfates (1-7) were isolated from the tropical sponge Dysidea sp. and their inhibitory activities against isocitrate lyase (ICL) from Candida albicans were evaluated. Among the isolated natural products compound 6 and 7 were found to be strong ICL inhibitors. The isolated compounds (1-7) also showed potent antibacterial effect against Bacillus subtilis and Proteus vulgaris, but did not display antifungal activity.     

Multiple approaches to enhance the cultivability of bacteria associated with the marine sponge Haliclona (gellius) sp

Three methods were examined to cultivate bacteria associated with the marine sponge Haliclona (gellius) sp.: agar plate cultures, liquid cultures, and floating filter cultures. A variety of oligotrophic media were employed, including media with aqueous and organic sponge extracts, bacterial signal molecules, and siderophores. More than 3,900 isolates were analyzed, and 205 operational taxonomic units (OTUs) were identified. Media containing low concentrations of mucin or a mixture of peptone and starch were most successful for the isolation of diversity, while the commonly used marine broth did not result in a high diversity among isolates. The addition of antibiotics generally led to a reduced diversity on plates but yielded different bacteria than other media. In addition, diversity patterns of isolates from agar plates, liquid cultures, and floating filters were significantly different. Almost 89% of all isolates were Alphaproteobacteria; however, members of phyla that are less commonly encountered in cultivation studies, such as Planctomycetes, Verrucomicrobia, and Deltaproteobacteria, were isolated as well. The sponge-associated bacteria were categorized into three different groups. The first group represented OTUs that were also obtained in a clone library from previously analyzed sponge tissue (group 1). Furthermore, we distinguished OTUs that were obtained from sponge tissue (in a previous study) but not from sponge isolates (group 2), and there were also OTUs that were not obtained from sponge tissue but were obtained from sponge isolates (group 3). The 17 OTUs categorized into group 1 represented 10 to 14% of all bacterial OTUs that were present in a large clone library previously generated from Haliclona (gellius) sp. sponge tissue, which is higher than previously reported cultivability scores for sponge-associated bacteria. Six of these 17 OTUs were not obtained from agar plates, which underlines that the use of multiple cultivation methods is worthwhile to increase the diversity of the cultivable microorganisms from sponges.