Axinella Verrucosa Research Articles

Barnacle fouling in the Mediterranean sponges Axinella polypoides and Axinella verrucosa

AbstractSecondary metabolites protect many marine sponges (Phylum: Porifera) from settlement by fouling organisms. Previous studies on the subtidal demosponge Axinella verrucosa collected in the Western Mediterranean led to the isolation of compounds that inhibited the settlement of cyprids larvae of the intertidal barnacle Balanus amphitrite, and the enzyme chitinase, which plays a key role in the molting cycle of crustaceans. However, in a field survey conducted at three locations in Israel, Eastern Mediterranean Sea, we observed that A. verrucosa is fouled by the subtidal barnacle Balanus trigonus, a previously unknown association. Settlement inhibition assays using B. amphitrite with chemical extracts from Israeli A. verrucosa and Axinella polypoides, a sympatric, congeneric sponge that seems not to be fouled by B. trigonus, showed that cyprid larvae of B. amphitrite were inhibited by the extracts of both sponges from settlement at concentrations several magnitudes lower than natural volumetric extract concentration in the sponges. These results indicate that, unlike the intertidal barnacle B. amphitrite, the subtidal B. trigonus is unaffected by the compounds from A. verrucosa, stressing and underlining the importance of using suitable target organisms (i.e. from the same habitat) to test for ecologically relevant antifouling activities.

Fulvitalea axinellae gen. nov., sp. nov., a member of the family Flammeovirgaceae isolated from the Mediterranean sponge Axinella verrucosa

The yellow-pigmented, non-motile, Gram-negative, strictly aerobic, rod-shaped bacterial strain VI.18(T) was isolated from the Mediterranean sponge Axinella verrucosa collected off the coast near Sdot Yam, Israel. Results from 16S rRNA gene sequence analysis indicated that the isolate belonged to the family Flammeovirgaceae. The highest nucleotide similarity (91.4 %) occurred with Aureibacter tunicatorum A5Q-118(T). The predominant cellular fatty acids of strain VI.18(T) were iso-C15 : 0 (56.0 %), iso-C17 : 1ω9c (22.8 %) and C16 : 0 (7.4 %) and its major respiratory quinone was MK-7. The DNA G+C content was 47.5 mol%. The strain could readily be distinguished from its phylogenetically closest relatives by phenotypic, physiological and chemotaxonomic properties. On the basis of the data from the present polyphasic study, we propose a novel genus and species within the family Flammeovirgaceae, with the name Fulvitalea axinellae gen. nov., sp. nov. Strain VI.18(T) ( = ATCC BAA-2395(T) = LMG 26722(T)) is the type strain of Fulvitalea axinellae.

Aureivirga marina gen. nov., sp. nov., a marine bacterium isolated from the Mediterranean sponge Axinella verrucosa

Two bacterial strains, VI.14 and VIII.04(T), were isolated from the Mediterranean sponge Axinella verrucosa collected off the Israeli coast near Sdot Yam. The non-motile, aerobic, Gram-negative isolates were oxidase-negative and catalase-positive, and formed golden-brown colonies on marine agar 2216. The pigment was neither diffusible nor flexirubin-like. Strain VIII.04(T) grew at 15-37 °C, at pH 6.0-9.0, in the presence of 20-50 g NaCl l(-1) and 20-80 g sea salts l(-1), The spectrum was narrower for strain VI.14, with growth at pH 7.0-8.0. and in the presence of 30-50 g NaCl l(-1) and 30-70 g sea salts l(-1). The predominant fatty acid (>50 %) in both strains was iso-C15 : 0, and the major respiratory quinone was MK-6. The DNA G+C content was 30.7 and 31.1 mol% for VIII.04(T) and VI.14, respectively. Results from 16S rRNA sequence similarity and phylogenetic analyses indicated that both strains are closely related to members of the family Flavobacteriaceae within the phylum Bacteroidetes, with as much as 91.7 % 16S rRNA sequence similarity. On the basis of data from the polyphasic analysis, we suggest that the strains represent a novel species in a new genus within the family Flavobacteriaceae, for which the name Aureivirga marina gen. nov., sp. nov. is proposed. Strain VIII.04(T) ( = ATCC BAA-2394(T) = LMG 26721(T)) is the type strain of Aureivirga marina.

Structure of debromo-carteramine A, a novel bromopyrrole alkaloid from the Mediterranean sponge Axinella verrucosa

The butanol extract of the Mediterranean sponge Axinella verrucosa was fractionated via a bioactivity-guided procedure based on an antibacterial assay. This approach led to the isolation of the novel alkaloid debromo-carteramine A 2 co-occurring with known hymenidin 1, the main antibacterial agent of the extract, and related inactive carteramine A 3.

Novel bioactive bromopyrrole alkaloids from the Mediterranean sponge Axinella verrucosa

The Mediterranean sponge Axinella verrucosa has been investigated for its alkaloid composition and has been found to produce a complex mixture of bromopyrrole alkaloids. Along with the previously isolated compounds 5–18, four novel alkaloids of this class, compounds 1–4, have been isolated, and their structures established through spectroscopic methods. Compounds 1–4 were found to display neuroprotective activity against the agonists serotonin and glutamate in vitro.

New communesin derivatives from the fungus Penicillium sp. derived from the Mediterranean sponge Axinella verrucosa.

The ethyl acetate extract of Penicillium sp., derived from the Mediterranean sponge Axinella verrucosa, yielded the known compound communesin B (1) and its new congeners communesins C (2) and D (3), as well as the known compounds griseofulvin, dechlorogriseofulvin, and oxaline. All structures were unambiguously established by 1D and 2D NMR and MS data. In several bioassays performed on different leukemia cell lines, the communesins exhibited moderate antiproliferative activity.

Biosynthetic studies of marine lipid 35. The demonstration of de novo sterol biosynthesis in sponges using radiolabeled isoprenoid precursors

1. 1. De novo sterol biosynthesis in the sponges Tethya aurantia and Aplysina fistularis was investigated, using sodium [5,5- 3H]-mevalonate, [1- 3H]-farnesol and [3- 3H]-Squalene was found to be the best precursor for demonstrating de novo sterol biosynthesis in a wider range of sponges. 2. 2. By feeding [3- 3H]-squalene and using cell-free techniques, the de novo sterol biosynthesis was established in 18 sponges belonging to nine orders. Among these sponges were Axinella polypoides and Axinella verrucosa which had previously been thought to be incapable of de novo sterol biosynthesis based on work with radiolabeled lanosterol, cycloartenol, mevalonate, and acetate. 3. 3. In contrast to earlier assumption, it is likely that all sponges are capable of de novo sterol biosynthesis.

An orange carotenoprotein from the marine sponge Axinella verrucosa (O. Schmidt). Purification and properties

1. 1. A carotenoid-protein complex was extracted by Triton X-100 and purified by Sephadex G 200 Fine and DEAE-Sephacel chromatography. 2. 2. This protein had a mol. wt of ca 640,000. SDS-polyacrylamide gel electropohresis showed only a single polypeptide chain with a mol. wat of ca 50,000. 3. 3. The molecule contains carbohydrates and lipids and at least six different carotenoids are present as prosthetic groups. 4. 4. The stability of the complex to the direct sunlight is quite low. 5. 5. The amino acid composition of the protein is briefly discussed.

Cellular aspects of alloimmune reactions in sponges of the genus Axinella II. Axinella verrucosa and Axinella damicornis

AbstractThe analysis and understanding of immune reactions in sponges are presently impaired by numerous discrepancies and inconsistencies between the results obtained for different species that make critical judgment difficult. In order to determine the possible influence of experimental procedures, parabiotic allografts were performed on Axinella verrucosa and Axinella damicornis. Three reactions were observed in allogrfts of Axinella verrucosa: acceptance, nonfusion, and chronic rejection. The acceptance reaction differed from the fusion of control autografts by a transient phase of dense cell accumulation between the parabionts. Nonfusion resulted in the virtual absence of reaction between the incompatible sponges. Chronic rejection was characterized by: 1) intensive cell migration and accumulation of collencytes in the zone of contact; 2) regular alignment of these cells on each side of that zone; 3) deposition of a collagen barrier that progressively joined but demarcated the parabionts. Some sponges presented nonfusion or chronic rejection depending on their graft partner. All allografts in Axinella damicornis displayed a chronic rejection reaction, which was essentially similar, but more intense and faster, than in Axinella verrucosa. However, in Axinella damicornis, the parabionts which were separated by the barrier became independent instead of joined. Reasons for and the implications of such a diversity of immune reactions in sponges are discussed.

Variability of allograft rejection processes in [formula omitted

Cellular aspects of histocompatibility in allografts of the sponge Axinella verrucosa have been studied. Three types of reactions were observed : 1) graft acceptance; 2) non-fusion, that is total absence of adherence between the sponges; 3) separative graft rejection, with strong adherence and fusion, followed by secretion of a dense collagen barrier between the sponges. These results clearly point out the variability of immune reactions in Axinella verrucosa .

Investigations on the ring contraction step in the biosynthesis of A-nor-stanols by the marine sponge Axinella verrucosa

The conversion of cholesterol into 3β-hydroxymethyl-A-nor-5α-cholestane by the sponge Axinella verrucosa involves the loss of 3α- and 4β-hydrogen atoms; the sponge also converts cholesterol into cholest-4-en-3-one and this conversion proceeds with loss of the 4β-hydrogen atom.

Pigments of the Porifera: Demospongiae. I. Carotenoids of Axinella verrucosa

Studies were made of some carotenoids extracted from Axinella verrucosa (O. schmidt) (Porifera: Demospongiae), a species which occurs in the Gulf of Naples. α-carotene, renieratene, isorenieratene, and an unknown isomer of renieratene have been isolated.

Marine sterols: unique 3β-hydroxymethyl-A-nor-5α-steranes from the sponge Axinella verrucosa

The total sterol content of the marine sponge Axinella verrucosa is a mixture of unique stanols containing a 3β-hydroxymethyl-A-nor-5α-cholestane nucleus with conventional C8, C9, and C10 side-chains.