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A diverse group of microbes is found to be present in aggregates within embryos of the tropical sponge Corticium sp. The results have confirmed the vertical transmission of multiple, phylogenetically diverse microorganisms in a marine sponge.

Results indicate that 2-n-pentyl-4-quinolinol is produced on the surfaces of an antibiotic-producing isolate of marine alteromonas sp. and generate a localized zone of high antibiotic concentration. The antibiotic interferes with metabolic processes of the bacterium leading to the altered composition of the bacterial community. This antibiosis process helps regulate the biogeochemical fate of ocean's organic matter.

Research has been conducted on the members of four phyla. The isolation of pyridoacridines from these members has been carried out via the laser-scanning confocal, epifluorescence and transmission electron microscopy, cell-separation techniques and chemical analysis and the results indicate that pyridoacridine alkaloid dercitamides are localized in bacteria-free sponge cells in Oceanapia sagittaria.

Research was conducted to examine adociasulfates 1-6, the inhibitors of kinesin motor proteins from the sponge Haliclona (aka Adocia) sp. The adociasulfates were isolated from an extract of the Palauan sponge Haliclona that inhibited the transport of stabilized microtubules by the motor protein kinesin that was immobilized on a microscope slide. Spectroscopic data determined the structures of adociasulfates 1-6, the relative stereochemistry of adociasulfates 1,2,5 and 6 and the relative stereochemistry of subunits of adociasulfates 3 and 4.

Symbiotic filamentous bacteria of the sponge Theonella swinhoei contain a major bicyclic peptide called theopalauamide. Proton nuclear magnetic resonance studies, gas chromatographic analysis and mass spectrometry were undertaken to determine its stereochemistry. The analysis of the degradation products of theopalauamide by chiral GC-MS helped in establishing the stereochemical characteristics of this compound.

It has been shown that ilimaquinone (IQ), a marine sponge metabolite, can cause vesiculation of the Golgi stacks. It has also been shown that the process does not require ARF and coatomers. IQ-mediated Golgi vesiculation was found to be inhibited by Galphas-GDP and Galpha13-GDP, and that the free Betagamma triggers Golgi vesiculation.

The isolation and characterization of four new alkaloids, batzelladines F-I, from the sponge Batzellia sp. are described. The compounds were isolated by a bioassay-directed fractionation technique. The alkaloids have been found to induce dissociation of the p56llkc-CDK complex at micromolar concentrations.

An ELISA-based assay reveals that two guanidine alkaloids, batzelladines A and B, of the Caribbean sponge Batzella sp. inhibit the HIV gp120-human CD4 binding. Extraction procedures enable the separation of five novel alkaloids, batzelladines A to E. Spectral analysis and chemical degradation studies help determine the structures of these alkaloids.

Spectroscopic analysis of theonegramide, an antifungal glycopeptide from the Philippine lithistid sponge Theonella swinhoei, shows that it contains an arabinose connected to a bicyclic dodecapeptide having unusual amino acids, and histidinoalanine. A comparative study between the structures of theongramide and theonellamide reveals similarities but four of the 12 amino acid residues are different. GC-MS analysis determines the absolute configuration of theonegramide using a chiral column packing.

A new type of polychlorinated amino acid obtained from Dysidea herbacea was separated and its structure was examined. 10-Dechlorodysideathiazole, 9,10-didechloro-N-methyldysideathiazole and 10-dechloro-N-methyldysideathiazole were separated from a Palauan specimen. The pattern of dysideathiazole-dysideapyrrolidone was described using spectroscopic techniques.

Ilimaquinone (IQ), a major metabolite of several dictyoceratid sponges, causes golgi membranes to break down into small vesicular structures called Vesiculated Golgi Membranes (VGM). IQ then inhibits vesicular protein transport by affecting an early step in the vesicle formation. IQ also causes depolarization of cytoplasmic microtubules.

The sponge Leucetta microraphis yields two antimicrobial lipids, leucettamols A and B, as active components of the pteridine alkaloid leucettidine. Spectroscopic analysis reveals the two as hexaenic conjugated polyols, possessing the characteristic optical inactivity of the leucettamols. Leucettamol A is assigned the molecular formula C30H52N2O2 and Leucettamol B, C30H52N2O3. Leucettamol B, a triol has one more secondary hydroxyl than A. The two are only mildly active against B. subtilis.

Spectral analysis of the compounds isolated from the Axinyssa aplysinoides marine sponge from Palau showed that the metabolites contained the thiocyanate (1R*,2R*,3R*,5R*,6S*,7S*)-2-thiocyanatopupukeanane. Moreover, two other specimens from Pohnpei, Caroline Islands, were examined using infrared and C NMR analyses. The first was found to contain the isothiocyanates, (1S*,2R*,5S*,6S*,7R*,8S*)-13-isothiocyanatocubebane and (1R*, 4S*,5R*,6S*,7S*,10R*)-1-isothiocyanatoaromadendrane, while the second was found to contain an axisonitrile-3 and a sesquiterpene thiocycanate with an unusual stereochemistry at C2.

X-ray studies of stellettamine, along with spectroscopic and metal-binding studies of the kuanoniamine D, prompt the revision of structures earlier reported for four related alkaloids. The structure of the thiazole moiety of dercitin, cyclodercitin, nordercitin, dercitamide and dercitamine was incorrectly reported for lack of a proper correlation technique at that time. The isolation and characterization of the kuanoniamines, where the thiazole structure is reversed, encouraged a reinvestigation of the dercitins. Apart from leading to structural revision, the new probe reveals that dercitamide and kuanoniamine C are one and the same.

The pyridoacridines neoamphimedine and amphimedine were isolated from Xestospongia sp. from the Philippines and Xestospongia cf. carbonaria from Micronesia. The chemical formula, chemical shifts and proton coupling pattern for amphimedine is the same as for amphimedine isolated by Schmitz and colleagues. Neoamphimedine was found to be cytotoxic to normal CHO AAS cells. It was also observed that neoamphimedine stimulates topoisomerase II dependent cleavage 3% above controls compared to etoposide, which stimulates 38% cleavage at the same concentration.

The large-scale isolation of manoalide from Luffariella variabilis yields secondary metabolites including (4E,6E)-dehydromanoalide and luffalactone, a tetracyclic sesterterpene acetate. The monoalide is a potent antiinflammatory agent and phospholipase A2 inhibitor. The metabolites are characterized following their coelution with dehydromanoalide during column chromatography. The bioactivity of (4E, 6E)-dehydromanoalide is already known while luffalactone, based on bioassays, is shown to exhibit 52% inhibition potency against edema.

The marine sponge Leucetta microrhaphis yields a new imidazole alkaloid along with the known clathridine zinc complex. The new metabolite, (9E)-clathridine 9-N-(2-sulfoethyl)imine, crystallizes as a yellow needle with a melting point of 275-277 degrees C. High-resolution mass measurement sets its molecular formula as C18H20N6O6S. Spectroscopic studies suggest a 1,3,4-trisubstituted benzene ring, with a methyleneoxy ring occupying the C-3 and C-4 positions. The major difference with the zinc complex is a two-carbon unit attached to ring A. An X-ray study also reveals a taurine residue at C-9 that hinders complexation with zinc.

Koshikamide B is isolated from two separate collections of the marine sponge Theonella sp. Its structure is determined by interpretation of spectral data and analysis of chemical degradation products.

The bacterial communities of the Palauan sponges Lamellodysidea herbacea, Lamellodysidea chlorea, Lendenfeldia chondrodes, and Phyllospongia papyacea known to be dominated by Oscillatoria spongeliae is investigated. Only Lendenfeldia chondrodes, and Phyllospongia papyacea are found to contain unusual alpha-proteobacteria with insertions present in a stem-loop of their rRNA.

Studies have revealed that protein kinase D is a downstream target of G(beta gamma) and plays a critical role in the regulation of Golgi structure and function. Initial experiments involved the analysis of the effects of a variety of inhibitors of protein kinases in an attempt to reveal the class of components that might be the downstream of G(beta gamma). Findings indicate that a possible mechanism by which the direct interaction of G(beta gamma) with protein kinase D regulates the dynamics of Golgi membranes and protein secretion.