Sandeep S Beepat
Victoria University of Wellington, School of Biological Sciences, Graduate Student
- University of Mauritius, Biosciences, Graduate Studentadd
The cellular mechanisms responsible for the regulation of nutrient exchange, immune response, and symbiont population growth in the cnidarian–dinoflagellate symbiosis are poorly resolved. Here, we employed liquid chromatography–mass... more
The cellular mechanisms responsible for the regulation of nutrient exchange, immune response, and symbiont population growth in the cnidarian–dinoflagellate symbiosis are poorly resolved. Here, we employed liquid chromatography–mass spectrometry to elucidate proteomic changes associated with symbiosis in Breviolum minutum, a native symbiont of the sea anemone Exaiptasia diaphana (‘Aiptasia’). We manipulated nutrients available to the algae in culture and to the holobiont in hospite (i.e., in symbiosis) and then monitored the impacts of our treatments on host–endosymbiont interactions. Both the symbiotic and nutritional states had significant impacts on the B. minutum proteome. B. minutum in hospite showed an increased abundance of proteins involved in phosphoinositol metabolism (e.g., glycerophosphoinositol permease 1 and phosphatidylinositol phosphatase) relative to the free-living alga, potentially reflecting inter-partner signalling that promotes the stability of the symbiosis. P...
Research Interests:
Research Interests:
The distribution and abundance of the sponge Spheciospongia vagabunda (Ridley, 1884) was investigated in a shallow lagoon (Albion) of Mauritius (Western Indian Ocean). Sponge abundance and environmental parameters were assessed. Sponges... more
The distribution and abundance of the sponge Spheciospongia vagabunda (Ridley, 1884) was investigated in a shallow lagoon (Albion) of Mauritius (Western Indian Ocean). Sponge abundance and environmental parameters were assessed. Sponges in Albion lagoon were mostly distributed in the central part of the lagoon some distance from wave action. Two distinctive sponge patches were found, the largest patch being 15350 m2 in area. Unlike most Porifera, S. vagabunda was mostly anchored in sand and not on hard substratum. A t-test revealed a significant difference in sponge size between sponge assemblages (t = 3.01; p < 0.05). One-way ANOVA indicated that environmental parameters did not influence sponge abundance within the lagoon (p <0.05). This study provides a baseline for future monitoring of these benthic animals in the Albion lagoon. Corresponding author: SSB Email: sann_1205@hotmail.com INTRODUCTION The Phylum Porifera is the oldest metazoan group found in our oceans (Müller, ...
Actinobacteria commonly known as actinomycetes are often constituents of the sponge-associated bacterial communities and are well known producers of bioactive compounds. In the present study, 7 actinomycete species representing 3 genera... more
Actinobacteria commonly known as actinomycetes are often constituents of the sponge-associated bacterial communities and are well known producers of bioactive compounds. In the present study, 7 actinomycete species representing 3 genera were successfully isolated from the sponge Spheciospongia vagabunda (Ridley, 1884) and Neopetrosia exigua (Kirkpatrick, 1900) from Mauritius. The sponge N. exigua hosted a higher actinomycete diversity resulting in 71% of the total number of actinomycete strains recorded. Streptomyces sp. and Micrococcus sp. were the most common actinomycete genera, both representing 43% of the total actinomycetes isolated from both host sponges. Actinomycete Isolation Agar was the most effective medium for the selection of actinobacteria, yielding in 57% of the total actinobacterial strains isolated. This study is the first to report on sponge-associated actinomycete communities from Mauritius and paves the way for future sponge-associated actinobacterial resea...
Research Interests:
Tropical lagoon-inhabiting organisms live in highly irradiated ecosystems and are particularly susceptible to thermal stress resulting from climate change. However, despite living close to their thermal maxima, stress response mechanisms... more
Tropical lagoon-inhabiting organisms live in highly irradiated ecosystems and are particularly susceptible to thermal stress resulting from climate change. However, despite living close to their thermal maxima, stress response mechanisms found in these organisms are poorly understood. We used a novel physiological-proteomic approach for sponges to describe the stress response mechanisms of the lagoon-inhabiting sponge Amphimedon navalis, when exposed to elevated seawater temperatures of +2 oC and +4 oC relative to a 26 oC ambient temperature for four weeks. After four weeks of thermal exposure, the buoyant weight of the sponge experienced a significant decline, while its pumping rates and oxygen consumption rates significantly increased. Proteome dynamics revealed 50 differentially abundant proteins in sponges exposed to elevated temperature, suggesting that shifts in the sponge proteome were potential drivers of physiological dysfunction. Thermal stress promoted an increase in deto...
Research Interests:
Research Interests:
Research Interests:
Actinobacteria, commonly known as actinomycetes, are often constituents of sponge-associated bacterial communities and are well known producers of bioactive compounds. In the present study, 7 actinomycete species representing 3 genera... more
Actinobacteria, commonly known as actinomycetes, are often constituents of sponge-associated bacterial communities and are well known producers of bioactive compounds. In the present study, 7 actinomycete species representing 3 genera were successfully isolated from the sponge Spheciospongia vagabunda (Ridley, 1884) and Neopetrosia exigua (Kirkpatrick, 1900) from Mauritius. Neopetrosia exigua hosted a higher actinomycete diversity resulting in 71% of the total number of actinomycete strains recorded. Streptomyces sp. and Micrococcus sp. were the most common actinomycete genera, both representing 43% of the total actinomycetes isolated from both host sponges. Actinomycete Isolation Agar was the most effective medium for the selection of actinobacteria, yielding in 57% of the total actinobacterial strains isolated. This study is the first to report on sponge-associated actinomycete communities from Mauritius and paves the way for future sponge-associated actinobacterial research in the Mascarene region.
Research Interests:
— The macrofaunal community associated with the sponge Neopetrosia exigua (Kirkpatrick, 1900) was studied across a Mauritian lagoon. A total of 191 macrofauna belonging to 18 macro-invertebrate species were found in association with host... more
— The macrofaunal community associated with the sponge Neopetrosia exigua (Kirkpatrick, 1900) was studied across a Mauritian lagoon. A total of 191 macrofauna belonging to 18 macro-invertebrate species were found in association with host sponges collected at depths of 1.4-2.7 m. Polychaetes and amphipods mostly inhabited the sponge canals whereas crabs and brittle stars were found at the base of the sponges. The most speciose taxon comprised Crustacea (61%, 11 spp.), followed by Polychaeta (33%, 6 spp.) and Echinodermata (6%, 1 sp.). The most dominant species was the polychaete Haplosyllis djiboutiensis (Gravier, 1900), comprising 71% of the specimens collected. There was, at best, moderately significant evidence that the number of macrofaunal species and individuals and their diversity index values were related to sponge volume and water depth. This sponge contributes to the maintenance of biodiversity in the lagoon by providing shelter and food for a number of invertebrates.