Submitted by Johnsson Rodrigo (r.johnsson@gmail.com) on 2013-09-02T12:00:59Z No. of bitstreams: 1 UESLEI.pdf: 2544719 bytes, checksum: 7b1f27c224c9b43ce55b5caf8f0d7c3f (MD5) / Approved for entry into archive by Alda Lima da Silva(sivalda@ufba.br) on 2013-09-26T18:22:30Z (GMT) No. of bitstreams: 1 UESLEI.pdf: 2544719 bytes, checksum: 7b1f27c224c9b43ce55b5caf8f0d7c3f (MD5) / Made available in DSpace on 2013-09-26T18:22:30Z (GMT). No. of bitstreams: 1 UESLEI.pdf: 2544719 bytes, checksum: 7b1f27c224c9b43ce55b5caf8f0d7c3f (MD5) / CNPq / Geodia gibberosa é uma das espécies que apresentam as maiores distribuições geográfica e batimétrica em comparação com suas congêneres. Com variações significativas na morfologia externa e no conjunto espicular, é considerada uma espécie com alto grau de polimorfismo e, muitas vezes, de difícil identificação. Tais características têm levado diversos pesquisadores a questionar os limites de sua variabilidade e a levantar hipóteses acerca da existência de espécies crípticas. Com o presente estudo, se objetivou avaliar o status taxonômico dessa espécie, aliando informações de morfologia e de biologia molecular, a qual empregou a utilização dos marcadores mitocondriais COI (subunidade I da citocromo c oxidase) e ATP6 (subunidade 6 da ATP sintase). Embora tenham sido observadas variações na morfologia das espículas e registradas categorias de megaescleras nunca vistas no holótipo, não foi possível encontrar nenhum padrão que possibilitasse a separação de G. gibberosa em espécies morfologicamente distintas. Contudo, através das ferramentas moleculares, foi determinada a existência de, pelo menos, três clados fortemente suportados, possibilitando a aceitação da hipótese de que G. gibberosa representa um complexo de espécies. Acrescido a isso, no presente trabalho, é descrita uma nova espécie de Geodia para a costa da Venezuela, com a apresentação de uma chave taxonômica para as 12 espécies nominais agora válidas que ocorrem no Caribe, e registrada a primeira ocorrência de Pachymatisma johnstonia para o oceano Atlântico ocidental. / Salvador

No description available.

The genera Spongia and Hippospongia include all of the commercially important bath sponges of the Caribbean fishery. This study examined the uniform presence of immense symbiotic bacterial populations of four of these species: Hippospongia lachne, Spongia barbara, S. cheiris and S. graminea. The nutritional characteristics and antibiotic sensitivities of bacteria isolated from the four species were also examined. A combined light and transmission electron microscopic investigation outlined the reproductive processes and larval development, behaviour, settlement and metamorphosis in these four species. / Symbiotic bacteria in these four sponge species are specific to the sponges and different from ambient seawater bacteria. Populations of intercellular bacteria within the tissues of these sponges are greater than those of ambient seawater. A variety of morphologically different types of sponge specific bacteria were observed. The symbionts are not fastidious organism but utilize a variety of amino acids, carbohydrates and tricarboxylic acid cycle intermediates as sole carbon and energy sources for growth. The bacteria showed sensitivities to a variety of antibiotics but were not susceptible to fluid from the sponges. / These sponges are viviparous and probably dioecious. Egg production and larval development are localized in patches or "nurseries" of endosomal tissue. Statistical analyses of specific morphological characteristics of female reproductive elements have identified four specific stages in the process of oogenesis. Umbilici connect young and maturing embryos to the maternal mesohyl and are the pathway for extracellular transfer of intercellular symbiotic bacteria and other mesohyl substances. These bacteria were observed in the embryos and larvae of all four species. Oocytes and embryos develop asynchronously within a given individual. Spermatogenesis occurs synchronously within cysts by transformation of entire choanocyte chambers. Cysts develop asynchronously within an individual. Male gametes exhibit a bright yellow-white autofluorescence when excited with blue light (460-485 nm). Spermatozoa do not possess intermediate segments or acrosomes. / The incubated parenchymella larvae of these four species are ovoid with dark grey pigmentation and enlarged posterior regions encircled by a black pigmented ring of cells bearing long cilia. Laboratory behavioural studies indicate that free-swimming larvae display directional swimming with constant rotation and negative phototaxis. Larval behaviour probably reflects the ecological situation of adult populations. Larval settlement occurs 26-56 hours after release and involves the rapid formation of a basal lamella between the larvae and substrate. There is no evidence of substrate selection or orientation by larvae. Precocious development of choanocytes does not occur in the larvae or post-larvae of these four species.

No description available.

Demosponges possess a skeleton made of a composite material with various organic constituents and/or siliceous spicules. Chitin is an integral part of the skeleton of different sponges of the order Verongida. Moreover, sponges of the order Verongida, such as Aplysina cavernicola or Ianthella basta, are well-known for the biosynthesis of brominated tyrosine derivates, characteristic bioactive natural products. It has been unknown so far whether these compounds are exclusively present in the cellular matrix or whether they may also be incorporated into the chitin-based skeletons. In the present study, we therefore examined the skeletons of A. cavernicola and I. basta with respect to the presence of bromotyrosine metabolites. The chitin-based-skeletons isolated from these sponges indeed contain significant amounts of brominated compounds, which are not easily extractable from the skeletons by common solvents, such as MeOH, as shown by HPLC analyses in combination with NMR and IR spectroscopic measurements. Quantitative potentiometric analyses confirm that the skeleton-associated bromine mainly withstands the MeOH-based extraction. This observation suggests that the respective, but yet unidentified, brominated compounds are strongly bound to the sponge skeletons, possibly by covalent bonding. Moreover, gene fragments of halogenases suggested to be responsible for the incorporation of bromine into organic molecules could be amplified from DNA isolated from sponge samples enriched for sponge-associated bacteria.

Demosponges possess a skeleton made of a composite material with various organic constituents and/or siliceous spicules. Chitin is an integral part of the skeleton of different sponges of the order Verongida. Moreover, sponges of the order Verongida, such as Aplysina cavernicola or Ianthella basta, are well-known for the biosynthesis of brominated tyrosine derivates, characteristic bioactive natural products. It has been unknown so far whether these compounds are exclusively present in the cellular matrix or whether they may also be incorporated into the chitin-based skeletons. In the present study, we therefore examined the skeletons of A. cavernicola and I. basta with respect to the presence of bromotyrosine metabolites. The chitin-based-skeletons isolated from these sponges indeed contain significant amounts of brominated compounds, which are not easily extractable from the skeletons by common solvents, such as MeOH, as shown by HPLC analyses in combination with NMR and IR spectroscopic measurements. Quantitative potentiometric analyses confirm that the skeleton-associated bromine mainly withstands the MeOH-based extraction. This observation suggests that the respective, but yet unidentified, brominated compounds are strongly bound to the sponge skeletons, possibly by covalent bonding. Moreover, gene fragments of halogenases suggested to be responsible for the incorporation of bromine into organic molecules could be amplified from DNA isolated from sponge samples enriched for sponge-associated bacteria.