Project description:Despite the fact that deep sea mining is becoming more popular nowadays in terms of obtaining metals ores for daily life purposes, its potential impact to the deep sea habitat, which is originally stable and converse, stills remains uncertain. In order to estimate and regulate the imapct of deep sea mining activities, an in-situ exposure experiment is performed to observe the change in proteomics expression of the deep-sea scvangers, Abyssorchomene distinctus, to copper exposure. This project aims to suggest a potenial protein bio-marker in Abyssorchomene distinctus to assess the impact of mining activities towards deep sea organisms and also discuss the potential application of other deep sea in-situ exposure experiment in the future.
Project description:Colonization of deep-sea hydrothermal vents by invertebrates was made efficient through their adaptation to a symbiotic lifestyle with chemosynthetic bacteria, the primary producers of these ecosystems. Anatomical adaptations such as the establishment of specialized cells or organs have been evidenced in numerous deep-sea invertebrates. However, very few studies detailed global inter-dependencies between host and symbionts in these ecosystems. In this study, we proposed to describe, using a proteo-transcriptomic approach, the effects of symbionts on the deep-sea mussel Bathymodiolus azoricus’ molecular biology. We induced an in situ depletion of symbionts and compared the proteo-transcriptome of the gills of mussels in three conditions: symbiotic mussels (natural population), symbiont-depleted mussels and aposymbiotic mussels
Project description:The available energy and carbon sources for prokaryotes in the deep ocean remain still largely enigmatic. Reduced sulfur compounds, such as thiosulfate, are a potential energy source for both auto- and heterotrophic marine prokaryotes. Shipboard experiments performed in the North Atlantic using Labrador Sea Water (~2000 m depth) amended with thiosulfate led to an enhanced prokaryotic dissolved inorganic carbon (DIC) fixation.
Project description:Physiological and gene expression studies of deep-sea bacteria under pressure conditions similar to those experienced in their natural habitat are critical to understand growth kinetics and metabolic adaptations to in situ conditions. The Epslilonproteobacterium, Nautilia sp. strain PV1, was isolated from hydrothermal fluids released from an active deep-sea hydrothermal vent at 9°N on the East Pacific Rise. Using a high pressure/high temperature continuous culture system we established that strain PV-1 has the shortest generation time of all known piezophilic microorganisms and we investigated its protein expression pattern in response to different hydrostatic pressures. Proteomic analyses of strain PV-1 grown at 200 Bars and 5 Bars showed that pressure adaptation is not restricted only to stress response or homeoviscous adaptation, but that it is more diversified and protein specific, with a fine and variegated regulation of enzymes involved even in the same metabolic pathway. As previously reported, proteins synthesis, motility, transport and energy metabolism are all affected by pressure, although to different extents. In strain PV-1, low pressure condition seems to activate the synthesis of phage-related proteins and an overexpression of enzymes involved in central carbon metabolism.