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Ecology And Physiology Of The Pathogenic Cyanobacterium Roseofilum Reptotaenium, Laurie L. Richardson, Dina Stanic, Amanda May, Abigael Brownell, Miroslav Gantar, Shawn R. Campagna
Ecology And Physiology Of The Pathogenic Cyanobacterium Roseofilum Reptotaenium, Laurie L. Richardson, Dina Stanic, Amanda May, Abigael Brownell, Miroslav Gantar, Shawn R. Campagna
Department of Biological Sciences
Roseofilum reptotaenium is a gliding, filamentous, phycoerythrin-rich cyanobacterium that has been found only in the horizontally migrating, pathogenic microbial mat, black band disease (BBD) on Caribbean corals. R. reptotaenium dominates the BBD mat in terms of biomass and motility, and the filaments form the mat fabric. This cyanobacterium produces the cyanotoxin microcystin, predominately MC-LR, and can tolerate high levels of sulfide produced by sulfate reducing bacteria (SRB) that are also associated with BBD. Laboratory cultures of R. reptotaenium infect coral fragments, suggesting that the cyanobacterium is the primary pathogen of BBD, but since this species cannot grow axenically and Koch’s …
Screening Of Cyanobacteria And Microalgae For Their Ability To Synthesize Silver Nanoparticles With Antibacterial Activity, Vijay Patel, David Berthold, Pravin Puranik, Miroslav Gantar
Screening Of Cyanobacteria And Microalgae For Their Ability To Synthesize Silver Nanoparticles With Antibacterial Activity, Vijay Patel, David Berthold, Pravin Puranik, Miroslav Gantar
Department of Biological Sciences
The aim of this study was to assess the ability of selected strains of cyanobacteria and microalgae to biosynthesize silver nanoparticles (Ag-NPs) by using two procedures; (i) suspending the live andwashed biomass of microalgae and cyanobacteria into the AgNO3 solution and (ii) by adding AgNO3 into a cellfree culture liquid. Ag-NPs were biosynthesized by 14 out of 16 tested strains. In most of the cases Ag-NPs were formed both in the presence of biomass as well as in the cell-free culture liquid. This indicates that the process of Ag-NPs formation involves an extracellular compound such as polysaccharide. TEM analysis showed …
Seagrasses In The Age Of Sea Turtle Conservation And Shark Overfishing, Michael R. Heithaus, Teresa Allcoverro, Rohan Arthur, Derek Burkholder, Kathryn A. Coates, Marjolijn J.A. Christianen, Nachiket Kelkar, Sarah A. Manuel, Aaron J. Wirsing, W. Judson Kenworthy, James W. Fourqurean
Seagrasses In The Age Of Sea Turtle Conservation And Shark Overfishing, Michael R. Heithaus, Teresa Allcoverro, Rohan Arthur, Derek Burkholder, Kathryn A. Coates, Marjolijn J.A. Christianen, Nachiket Kelkar, Sarah A. Manuel, Aaron J. Wirsing, W. Judson Kenworthy, James W. Fourqurean
Department of Biological Sciences
Efforts to conserve globally declining herbivorous green sea turtles have resulted in promising growth of some populations. These trends could significantly impact critical ecosystem services provided by seagrass meadows on which turtles feed. Expanding turtle populations could improve seagrass ecosystem health by removing seagrass biomass and preventing of the formation of sediment anoxia. However, overfishing of large sharks, the primary green turtle predators, could facilitate turtle populations growing beyond historical sizes and trigger detrimental ecosystem impacts mirroring those on land when top predators were extirpated. Experimental data from multiple ocean basins suggest that increasing turtle populations can negatively impact seagrasses, …
The Dangers Of Carbon-Centric Conservation For Biodiversity: A Case Study In The Andes, Alvaro Duque, Kenneth J. Feeley, Edersson Cabrera, Ricardo Callejas, Alvaro Idarraga
The Dangers Of Carbon-Centric Conservation For Biodiversity: A Case Study In The Andes, Alvaro Duque, Kenneth J. Feeley, Edersson Cabrera, Ricardo Callejas, Alvaro Idarraga
Department of Biological Sciences
Carbon-centric conservation strategies such as the United Nation’s program to Reduce CO2 Emissions from Deforestation and Degradation (REDD+), are expected to simultaneously reduce net global CO2 emissions and mitigate species extinctions in regions with high endemism and diversity, such as the Tropical Andes Biodiversity Hotspot. Using data from the northern Andes, we show, however, that carbon-focused conservation strategies may potentially lead to increased risks of species extinctions if there is displacement (i.e., “leakage”) of land-use changes from forests with large aboveground biomass stocks but relatively poor species richness and low levels of endemism, to forests with lower biomass stocks but …
Genetic Diversity And Demographic History Of Cajanus Spp. Illustrated From Genome-Wide Snps, Rachit K. Saxena, Eric Von Wettberg, Hari D. Upadhyaya, Vanessa Sanchez, Serah Songok, Kulbhushan Saxena, Paul Kimurto, Rajeev K. Varshney
Genetic Diversity And Demographic History Of Cajanus Spp. Illustrated From Genome-Wide Snps, Rachit K. Saxena, Eric Von Wettberg, Hari D. Upadhyaya, Vanessa Sanchez, Serah Songok, Kulbhushan Saxena, Paul Kimurto, Rajeev K. Varshney
Department of Biological Sciences
Understanding genetic structure of Cajanus spp. is essential for achieving genetic improvement by quantitative trait loci (QTL) mapping or association studies and use of selected markers through genomic assisted breeding and genomic selection. After developing a comprehensive set of 1,616 single nucleotide polymorphism (SNPs) and their conversion into cost effective KASPar assays for pigeonpea (Cajanus cajan), we studied levels of genetic variability both within and between diverse set of Cajanus lines including 56 breeding lines, 21 landraces and 107 accessions from 18 wild species. These results revealed a high frequency of polymorphic SNPs and relatively high level of cross-species transferability. …
Starvation Increases Insulin Sensitivity And Reduces Juvenile Hormone Synthesis In Mosquitoes, Meritxell Perez-Hedo, Crisalejandra Rivera-Perez, Fernando G. Noriega
Starvation Increases Insulin Sensitivity And Reduces Juvenile Hormone Synthesis In Mosquitoes, Meritxell Perez-Hedo, Crisalejandra Rivera-Perez, Fernando G. Noriega
Department of Biological Sciences
Background: The interactions between the insulin signaling pathway (ISP) and juvenile hormone (JH) controlling reproductive trade-offs are well documented in insects. JH and insulin regulate reproductive output in mosquitoes; both hormones are involved in a complex regulatory network, in which they influence each other and in which the mosquito’s nutritional status is a crucial determinant of the network’s output. Previous studies reported that the insulin-TOR (target of rapamacyn) signaling pathway is involved in the nutritional regulation of JH synthesis in female mosquitoes. The present studies further investigate the regulatory circuitry that controls both JH synthesis and reproductive output in response …
Experimental Evidence Of Threat-Sensitive Collective Avoidance Responses In A Large Wild-Caught Herring School, Guillaume Rieucau, Kevin M. Boswell, Alex De Robertis, Gavin J. Macaulay, Nils Olav Handegard
Experimental Evidence Of Threat-Sensitive Collective Avoidance Responses In A Large Wild-Caught Herring School, Guillaume Rieucau, Kevin M. Boswell, Alex De Robertis, Gavin J. Macaulay, Nils Olav Handegard
Department of Biological Sciences
Aggregation is commonly thought to improve animals’ security. Within aquatic ecosystems, group-living prey can learn about immediate threats using cues perceived directly from predators, or from collective behaviours, for example, by reacting to the escape behaviours of companions. Combining cues from different modalities may improve the accuracy of prey antipredatory decisions. In this study, we explored the sensory modalities that mediate collective antipredatory responses of herring (Clupea harengus) when in a large school (approximately 60 000 individuals). By conducting a simulated predator encounter experiment in a semi-controlled environment (a sea cage), we tested the hypothesis that the collective responses of …
Photosynthetic Activity Buffers Ocean Acidification In Seagrass Meadows, I. E. Hendriks, Y. S. Olsen, L. Ramajo, L. Basso, T. S. Moore, J. Howard, C. M. Duarte
Photosynthetic Activity Buffers Ocean Acidification In Seagrass Meadows, I. E. Hendriks, Y. S. Olsen, L. Ramajo, L. Basso, T. S. Moore, J. Howard, C. M. Duarte
Department of Biological Sciences
Macrophytes growing in shallow coastal zones characterised by intense metabolic activity have the capacity to modify pH within their canopy and beyond. We observed diel pH changes in shallow (5–12 m) seagrass (Posidonia oceanica) meadows spanning 0.06 pH units in September to 0.24 units in June. The carbonate system (pH, DIC, and aragonite saturation state (ΩAr)) and O2 within the meadows displayed strong diel variability driven by primary productivity, and changes in chemistry were related to structural parameters of the meadow, in particular, the leaf surface area available for photosynthesis (LAI). LAI was positively correlated …
There Are Many Barriers To Species’ Migrations, Kenneth J. Feeley, Evan M. Rehm, James T. Stroud
There Are Many Barriers To Species’ Migrations, Kenneth J. Feeley, Evan M. Rehm, James T. Stroud
Department of Biological Sciences
Temperature-change trajectories are being used to identify the geographic barriers and thermal ‘cul-de-sacs’ that will limit the ability of many species to track climate change by migrating. We argue that there are many other potential barriers to species’ migrations. These include stable ecotones, discordant shifts in climatic variables, human land use, and species’ limited dispersal abilities. To illustrate our argument, for each 0.5° latitude/longitude grid cell of the Earth’s land surface, we mapped and tallied the number of cells for which future (2060–2080) climate represents an analog of the focal cell’s current climate. We compared results when only considering temperature …