Project description:The red seaweed, Asparagopsis taxiformis, is a promising ruminant feed-additive with significant anti-methanogenic properties, which could provide a global solution to climate-change. Emerging genomics in this species has provided a strong foundation for in-depth molecular investigations, including proteomics. Here, we investigated the A. taxiformis (L6) proteome of sporophyte and gametophyte (male and female), using soluble and insoluble extraction methods followed by mass spectrometry. A combined total of 741 and 2007 unique non-redundant proteins were identified using genome-derived and transcriptome-derived databases, respectively. Genome-derived proteins were used for further analysis including a relatively large proportion of proteins that were annotated as ion binding proteins (i.e. iron, zinc, manganese, potassium and copper), which may play a role in heavy metal bioremediation. In addition, we identified 44 photosynthesis-related proteins (e.g. phycobilisomes, photosystem I, photosystem II and ATPase) and 58 stress-related proteins (e.g. heat shock proteins and vanadium-dependent haloperoxidases). Forty proteins were predicted to be secreted, supporting a role for them in extracellular activities such as mucilage development and defence. Two Gal-2,6-Sulfurylases II proteins are likely necessary for carrageenan biosynthesis, as well as development of reproductive-associated structures. These findings provide a comprehensive overview of expressed proteins in A. taxiformis (L6) at two different life stages, highlighting the potential of proteomic approaches and warrant further studies for understanding protein functions.
Project description:Asparagopsis taxiformis (Rhodophyta) is a species of red algae belonging to the family Bonnemaisoniaceae. The objective of the present study was to evaluate antioxidant and antiproliferative activity of four fractions (petroleum ether, chloroform, ethyl acetate, and methanol) of A. taxiformis.The red seaweed, A. taxiformis was collected from Mandapam Coastal Region, Gulf of Mannar, Tamil Nadu. Epiphytes present in algal extracts were cleaned and washed with seawater and fresh water. In vitro antioxidant activity was determined by hydrogen peroxide scavenging, ferric reducing antioxidant power, superoxide radical, metal-chelating activity, and phosphomolybdenum reduction assay. Further, the cytotoxic activity was evaluated using brine shrimp lethality assay. This method is rapid, reliable, inexpensive, and convenient as compared to other cytotoxicity assays. Gallic acid, ethylenediaminetetraacetic acid, ascorbic acid, and quercetin were used as reference antioxidant compounds.Reducing power of chloroform extract increased with increasing concentration of the extract. The radical scavenging activity of extracts was in the following order: ascorbic acid > methanol > chloroform > petroleum ether > ethyl acetate. Highest metal-chelating activity was observed in petroleum ether fractions (63%). Reduction of Mo (VI) to Mo (V) increased in methanol extract (27%) at 100 μg/ml. Moreover, all fractions had an inhibitory effect on the formation of hydroxyl radicals. Results showed that ethyl acetate, methanol, and petroleum ether fractions exhibited potent cytotoxic activity with median lethal concentration values of 84.33, 104.4, and 104.4 μg/ml, respectively.Thus, the results showed that red algae possess strong antioxidant and cytotoxic activity that suggests their possible use in the development of pharmaceutical drugs.Various fractions of red algae Asparagopsis taxiformis was evaluated for in vitro antioxidant and antiproliferative studies. All results indicate potential use of red algae for drug development. Abbreviations Used: Mo: Molybdenum, AlCl3.H2O: Aluminum chloride, NaNO2: Sodium nitrite, NaOH: Sodium hydroxide, H2O2: Hydrogen peroxide, NADH: Nicotinamide adenine dinucleotide, NBT: Nitroblue tetrazolium chloride, PMS: Phenyl methanesulfonate, FeCl2: Ferrous chloride.