Searching for new bioactive metabolites from the bacterial genus is a challenging task. Combined genomic tools and metabolomic screening of spp. native to extreme environments could be a promising strategy to discover novel compounds.
View Article and Find Full Text PDFThe coral-killing invasive sponge, Terpios hoshinota, causes extensive mortality to live corals and is a potential threat to reefs at different geographical locations. However, to date, the invasive mechanism remains largely unknown. In this study, we aimed to understand the bacterial competition between sponge and coral hosted bacteria when sponge outcompetes corals.
View Article and Find Full Text PDFCoral bleaching, a phenomenon by which the expulsion of corals' alveolate endosymbiont (zooxanthellae) occurs when experiencing thermal stress is the major cause for devastation of corals. However, apart from this obligate symbiont of Scleractinian corals, there are different kinds of microbes that exist as stable, transient or sporadic members of the holobiont which reside within various microhabitats in the coral structures. Thus, this study aims to profile the coral bacterial community composition among different coral genera (thermally-sensitive (Acropora digetifera and A.
View Article and Find Full Text PDFInformation about coral community response to bleaching on Indian reefs is much more limited compared with Indo-Pacific reefs, with no understanding of algal symbionts. We investigated a reef in Palk Bay to understand the coral community response to 2016 bleaching event and to reveal dominant symbiont type association in four common coral genera. Out of 508 colonies surveyed, we found 20.
View Article and Find Full Text PDFWorldwide, reef building corals are being degraded due to increasing anthropogenic pressure, and as a result, macroalgal cover is being increased. Hence, mechanism of coral-algal interaction, differential coral response to algal overgrowth, is critical from every geographical location to predict future coral dynamics. This paper documents the frequency of coral-algal (Halimeda) interactions, differential coral response to algal interaction.
View Article and Find Full Text PDFInvestigating the bacterial diversity and their metabolic capabilities are crucial for interpreting ecological patterns in desert environment, and assessing the presence of exploitable microbial resources. In this study, we evaluated the spatial heterogeneity of physico-chemical parameters, soil bacterial diversity and metabolic adaptation at meter scale. Soil samples were collected from two quadrates a desert environment (Thar Desert, India) which face hot arid climate with very little rainfall and extreme temperatures.
View Article and Find Full Text PDFSponges are sessile benthic filter-feeding animals, which harbor numerous microorganisms. The enormous diversity and abundance of sponge associated bacteria envisages sponges as hot spots of microbial diversity and dynamics. Many theories were proposed on the ecological implications and mechanism of sponge-microbial association, among these, the biosynthesis of sponge derived bioactive molecules by the symbiotic bacteria is now well-indicated.
View Article and Find Full Text PDFAcquisition of Actinobacteria, especially from previously underexplored habitats and the exploration of their biosynthetic potential have gained much attention in the rejuvenated antibiotics search programs. Herein, we isolated some strains, from an arid region of the Great Indian Thar Desert, which possess an ability to produce novel bioactive compounds. Twenty-one morphologically distinctive strains differing in their aerial and substrate mycelium were isolated by employing a stamping method.
View Article and Find Full Text PDFCorals are hotspots of ocean microbial diversity and imbalance in the composition of coral associated microbes has been mostly correlated with the emergence of climate change driven diseases which affect the overall stability of the reef ecosystem. Coral sampling was performed by SCUBA diving at Palk Bay (latitude 9.271580, longitude 79.
View Article and Find Full Text PDFAcropora white syndrome (AWS) and Terpios sponge overgrowth (TSO) are serious threats to coral communities in various regions; however, information on these 2 lesions in the Indian Ocean is much more limited than in the Indo-Pacific. The present study revealed the impact of these lesions on the Palk Bay reef, India, and covered an area of 7 km2. In total, 1930 colonies were permanently monitored to assess incidences of AWS and TSO and consequent mortality for a period of 1 yr.
View Article and Find Full Text PDFThe coral-killing sponge, Terpios hoshinota is a global invasive species that has conquered coral patches within a short span of time, which has led to a significant decline in living coral cover at various geographical locations. In this study, we surveyed the linear progression and impact of the Terpios invasion on live coral patches along Palk Bay, Indian Ocean, from August 2013 to August 2015. The field inventory revealed an extensive fatality rate of 76% as a result of Terpios outbreak.
View Article and Find Full Text PDFChitosan was extracted from the pen of squid Doryteuthis singhalensis and characterized using FT-IR, NMR, CHN, SEM and DSC analysis. Purified chitosan was sulfated with chlorosulfonic acid in N,N-dimethylformamide and the added sulfate group was confirmed with FT-IR analysis. The molecular weight and degree of deacetylation (DDA) of chitosan was found 226.
View Article and Find Full Text PDFInformation on the progression of coral diseases and transmission to live corals is scarce despite the fact that coral disease poses one of the most lethal threats to the survival of coral reefs. In this study, in situ progression rates of lesions similar to black band disease (BBD) and white band disease (WBD) were measured in different species of corals from the Gulf of Mannar (GoM) and Palk Bay, southeastern India, during the period between January and December of 2009. Maximum progression rates of 3 and 1.
View Article and Find Full Text PDFThe present study reports coral mortality, driven primarily by coral diseases, around Shingle Island, Gulf of Mannar (GOM), Indian Ocean. In total, 2910 colonies were permanently monitored to assess the incidence of coral diseases and consequent mortality for 2 yr. Four types of lesions consistent with white band disease (WBD), black disease (BD), white plaque disease (WPD), and pink spot disease (PSD) were recorded from 4 coral genera: Montipora, Pocillopora, Acropora, and Porites.
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