Abstract Teredinidae (shipworms) is a family of marine wood-boring bivalves that has an important role in the degradation of wood through its symbiotic relationship with cellulolytic bacteria. To evaluate the rate of degradation of wood by teredinids in two sites with different oceanographic conditions in Rio de Janeiro State, Brazil, artificial structures composed of pine wood sheets were immersed in the ocean for three months at Arraial do Cabo in an area under the influence of upwelling, and at Ilha Grande Bay under tropical and oligotrophic influences. After the immersion period, teredinids were removed from the collectors, identified, and counted. Wood consumption by the teredinids was quantified by comparing the dry weights of the collectors before and after immersion. Associated bacteria were isolated and their cellulolytic activities evaluated at different temperatures and salinities. Two Teredinidae species were recorded: Bankia gouldi and Lyrodus floridanus. The highest wood degradation rate and enzymatic activities of the isolated bacterial strains were recorded at Arraial do Cabo, suggesting that upwelling influenced the activities of those species.

ABSTRACT Marine sponges has been a large reservoir of microbial diversity, with the presence of many species specific populations as well as producing biologically active compounds, which has attracted great biotechnological interest. In order to verify the influence of the environment in the composition of the bacterial community present in marine sponges and biotechnological potential of bacteria isolated from these organisms, three species of sponges and the waters surrounding them were collected in different beaches of Rio de Janeiro, Brazil. The profile of the bacterial community present in sponges and water was obtained by PCR-DGGE technique and the biotechnological potential of the strains isolated by producing amylase, cellulase, protease and biosurfactants. The results showed that despite the influence of the environment in the composition of the microbial community, studied marine sponges shown to have specific bacterial populations, with some, showing potential in the production of substances of biotechnological applications.

RESUMOOs sistemas de ressurgência possuem uma grande diversidade de microrganismos pelágicos e sua composição e atividade são determinadas por fatores como a temperatura e a concentração de nutrientes. A técnica de Electroforese em Gel por Gradiente Desnaturante (EGGD) foi utilizada para verificar a variabilidade genética espacial e temporal de Bacteria e Archea em duas estações na costa da região de Arraial do Cabo; uma com maior pressão da ressurgência, e a outra sobre pressão antropogênica. Além disso, as variáveis bióticas e abióticas foram medidas nas águas superficiais e de fundo de outras três estações situadas entre essas estações. Seis amostragens foram realizadas durante um ano e representaram adequadamente os diferentes graus de ressurgência e de pressões antropogênicas no sistema. A Análise por Componente Principal (ACP) mostrou uma correlação negativa entre a concentrações de amônia e de fósforo e a produção secundária procariótica e o total de bactérias heterotróficas. A ACP também mostrou uma correlação negativa entre a temperatura e a abundância de células procarióticas. As composições de Bacteria e Archaea foram variáveis, assim como as condições oceanográficas, e a ressurgência teve uma pressão regional enquanto a pressão antropogênica foi pontual. Sugerimos que as medidas de produção secundária procariótica esteve associada à atividade de ambas Bacteria e Archaea, e que a disponibilidade de substrato e a temperatura determinam a ciclagem de nutrientes.

ABSTRACTUpwelling systems contain a high diversity of pelagic microorganisms and their composition and activity are defined by factors like temperature and nutrient concentration. Denaturing gradient gel electrophoresis (DGGE) technique was used to verify the spatial and temporal genetic variability of Bacteria and Archaea in two stations of the Arraial do Cabo coastal region, one under upwelling pressure and another under anthropogenic pressure. In addition, biotic and abiotic variables were measured in surface and deep waters from three other stations between these stations. Six samplings were done during a year and adequately represented the degrees of upwelling and anthropogenic pressures to the system. Principal Component Analysis (PCA) showed negative correlations between the concentrations of ammonia and phosphorous with prokaryotic secondary production and the total heterotrophic bacteria. PCA also showed negative correlation between temperature and the abundance of prokaryotic cells. Bacterial and archaeal compositions were changeable as were the oceanographic conditions, and upwelling had a regional pressure while anthropogenic pressure was punctual. We suggest that the measurement of prokaryotic secondary production was associated with both Bacteria and Archaea activities, and that substrate availability and temperature determine nutrients cycling.