Symbiont Dependent Host Reproduction In The Marine Bryozoan, Bugula neritina

Larvae of the marine bryozoan, Bugula neritina, are defended from predation by the bryostatins, polyketides synthesized by its uncultured endosymbiont, “Candidatus Endobugula sertula.” Bryostatins are potent modulators of the eukaryotic signaling protein, protein kinase C (PKC) that is involved in many eukaryotic cellular processes. The close association of the host and symbiont raises the possibility of an interaction between the symbiont-produced bryostatins and host PKCs. Such interaction could impact PKC regulated host cellular processes, which could result in altered host physiology. In this study, I investigated the response of the bryozoan host in the absence of the symbiont and symbiont-produced bryostatins. Western blot analysis of protein extracts from symbiotic and symbiont-reduced B. neritina colonies revealed a difference in bryostatin-activated conventional PKCs, but none for bryostatin-independent PKCs. Similar results were observed for PKCs in the model invertebrate, Caenorhabditis elegans, exposed to bryostatin, suggesting that the symbiont-produced bryostatins potentially modulate PKC activity and therefore PKC-mediated cellular processes in symbiotic B. neritina and bryostatin-exposed C. elegans. The number of ovicell-bearing female zooids in symbiont-reduced colonies was significantly decreased, suggesting a role of symbiont in the host reproduction. Interestingly, the female zooids in both the colony types were healthy and no anatomical or molecular differences were found except that fewer female zooids occur in symbiont-depleted colonies. The lack of difference in female zooids indicate that the symbiont does not affect the female structures and functions in the zooid, but potentially influences the early stage differentiation of the female zooid in the colony. I hypothesize that symbiont-produced bryostatins via PKC activation signal early stage differentiation of the female zooids in the colony. Additionally, microscopic investigation revealed the presence of previously undescribed ‘funicular bodies’ containing bacteria in the symbiotic colonies. However, the bacteria associated with the ‘funicular bodies’ and funicular strands in the symbiotic colonies were morphologically different and are potentially an adaptation for successful mutualistic association with the bryozoan host

Differential Gene Expression in Bugula Neritina during Symbiotic Association with Candidatus Endobugula Sertula

The colonial marine bryozoan, Bugula neritina, harbors an uncultured endosymbiont, “Candidatus Endobugula sertula” throughout its life stages. The bacterial symbiont has been proposed to be a source of complex polyketide metabolites, the bryostatins, that chemically defend B. neritina larvae from predation. Within a bryozoan colony, significantly higher amounts of bryostatins are found in ovicell-bearing zooids where the developing larvae are brooded, as compared to ovicell-free zooids. It is hypothesized that signaling between B. neritina and “Ca. Endobugula sertula” may be involved in the regulation of bryostatin production in different zooids, as well as in maintenance of the symbiosis. In this study, suppression subtractive hybridization (SSH) was used to identify differentially expressed host genes during this association. The identified genes suggest that the host plays a role in the distribution and localization of bacterial symbionts in different host zooids, possibly to regulate levels of bryostatin production in the zooids

Engineering the Properties of Indium Sulfide for Thin Film Solar Cells by Doping

In the present work, structural, optical and electrical properties of indium sulfide are tuned by specific and controlled doping. Silver, tin, copper and chlorine were used as the doping elements. In2S3 thin films for the present study were prepared using a simple and low cost “Chemical Spray Pyrolysis (CSP)” technique. This technique is adaptable for large-area deposition of thin films in any required shape and facilitates easiness of doping and/or variation of atomic ratio. It involves spraying a solution, usually aqueous, containing soluble salts of the constituents of the desired compound onto a heated substrate. Doping process was optimized for different doping concentrations. On optimizing doping conditions, we tuned the structural, optical and electrical properties of indium sulfide thin films making them perform as an ideal buffer layer.Department of Physics, Cochin University of Science and Technolog

Photocatalytic activities of SnS thin films deposited at room temperature

Tin monosulfide (SnS) thin films were deposited on glass substrates at room temperature utilising a simple, inexpensive, and modified chemical approach known as Successive Layer Adsorption and Reaction (SLAR). The properties of the films were thoroughly studied using an XRD, SEM, EDAX, and UV-VIS spectrophotometer. It was possible to deposite smooth, homogeneous, and uniform thin films with pollycrystalline nature, orthorombic structure, and UV-VIS absorption. Under visible light irradiation, SnS thin films demonstrated high photocatalytic degradation of Methylene Blue. It showed effective degradation of a common textile dye available in the marker as well. Dye degradation was found to be of first order, following the Langmuir-Hinshelwood mechanism. Theoretical band structure calculations suggested that the relative positions of the highest valence band and lowest conduction band were 1.605 eV and -0.085 eV, respectively. The photocatalyst's reusability, the involvement of the hydroxyl radical in photodegradation, and the variation in photocatalytic performance of SnS thin films with dye solution pH and initial dye concentration were all examined. Changes in the cationic precursor's molarity caused changes in the thin film's crystallinity, stoichiometry, and bandgap. Non-stoichiometric films demonstrated higher photocatalytic activity

Hexavalent chromium removal using reduced graphene oxide-zinc oxide composite fabricated via simple pyrolysis method

The contamination of water by heavy metals from various industrial effluents is a significant factor contributing to the scarcity of clean water worldwide. To address this issue, there is a need to develop low-cost adsorbents to remove heavy metals from contaminated water reduced graphene oxide (rGO) based composites are efficient adsorbers of heavy metals. In this study, a green and rapid single-step heating process was utilized to prepare both rGO and rGO/ZnO composite materials, avoiding the use of any toxic reagents. The rGO/ZnO composite synthesized from sucrose and zinc acetate demonstrates a remarkable ability to adsorb hexavalent chromium (Cr(VI)). The Cr adsorption studies were carried out by varying adsorbent, contact time, initial pH, and concentration. The adsorption efficiency of the composite is five times higher than that of pure rGO. The adsorption mechanism of Cr(VI) onto the adsorbent is electrostatic interaction, complexation, pore filling, and reduction, identified through Zeta potential measurement, BET, EDX, and XPS analysis. These studies suggest that rGO/ZnO composite has great potency as a cost-effective and efficient adsorbent for removing Cr(VI) contaminants from industrial effluents

Effect of nutrient nitrogen on laccase production, its isozyme pattern and effluent decolorization by the fungus NIOCC #2a, isolated from mangrove wood. Indian

Carbon and nitrogen sources in the growth medium play an important role in the production of lignin-degrading enzymes in the white-rot basidiomyceteous fungi. The role of nutrient nitrogen sources in growth media on production of lignin-degrading enzymes namely laccase, lignin peroxidase and manganese peroxidase as well as on the decolorization of industrial effluents like black liquor, molasses spent wash and textile mill effluents was studied using the basidiomycetous fungus NIOCC #2a isolated from mangrove wood. The results indicated that the type of nitrogen source used, not only influences the amount and type of lignin-degrading enzymes produced but also has an effect on the decolorization of these effluents. The amount of extracellular peroxidases increased by several fold in the presence of effluents whereas in their absence they were of negligible quantity. Some of the effluents had an inhibitory effect on laccase production. The effect of nitrogen sources in the absence as well as presence of the effluents, on the expression of laccase isoenzymes was studied by non-denaturing SDS-PAGE. It was noticed that a few new isozymes of laccase were induced in the presence of industrial effluents. Decolorization of these effluents by the concentrated culture filtrate obtained from media containing different nitrogen sources further proved the importance of the type of nitrogen source in decolorization of colored industrial effluents

Effect of nutrient nitrogen on laccase production, its isozyme pattern and effluent decolorization by the fungus NIOCC #2a, isolated from mangrove wood

364-372Carbon and nitrogen sources in the growth medium play an important role in the production of lignin-degrading enzymes in the white-rot basidiomyceteous fungi. The role of nutrient nitrogen sources in growth media on production of lignin-degrading enzymes namely laccase, lignin peroxidase and manganese peroxidase as well as on the decolorization of industrial effluents like black liquor, molasses spent wash and textile mill effluents was studied using the basidiomycetous fungus NIOCC #2a isolated from mangrove wood. The results indicated that the type of nitrogen source used, not only influences the amount and type of lignin-degrading enzymes produced but also has an effect on the decolorization of these effluents. The amount of extracellular peroxidases increased by several fold in the presence of effluents whereas in their absence they were of negligible quantity. Some of the effluents had an inhibitory effect on laccase production. The effect of nitrogen sources in the absence as well as presence of the effluents, on the expression of laccase isoenzymes was studied by non-denaturing SDS-PAGE. It was noticed that a few new isozymes of laccase were induced in the presence of industrial effluents. Decolorization of these effluents by the concentrated culture filtrate obtained from media containing different nitrogen sources further proved the importance of the type of nitrogen source in decolorization of colored industrial effluents

Role of chlorine on the opto-electronic properties of β-In2S3 thin films

Effect of chlorine doping on the opto-electronic properties of β-In2S3 thin film, deposited by spray pyrolysis technique is studied for the first time. Chlorine was incorporated in the spray solution, using HCl. Pristine sample prepared using In(NO3)3 and thiourea as the precursors showed very low photosensitivity. But upon adding optimum quantity of chlorine, the photosensitivity increased by 3 orders. X-ray analysis revealed that crystallinity was also increasing up to this optimum level of Cl concentration. It was also observed that samples with high photosensitivity were having higher band gap. The present study proved that doping with chlorine was beneficial as this could result in forming crystalline and photosensitive films of indium sulfide.Cochin University of Science and TechnologyThin Solid Films 518 (2010) 1779–178

Additional file 1 of Inferring metabolic pathway activity levels from RNA-Seq data

Supplementary table. The Supplementary table is supplied in PDF format. (PDF 16 kb