scholarly journals Sponge–Microbe Interactions on Coral Reefs: Multiple Evolutionary Solutions to a Complex Environment

2021 ◽  
Vol 8 ◽  
Author(s):  
Christopher J. Freeman ◽  
Cole G. Easson ◽  
Cara L. Fiore ◽  
Robert W. Thacker
Keyword(s):  
Coral Reefs ◽  
Marine Sponges ◽  
Future Research ◽  
Ecological Niches ◽  
Trade Offs ◽  
Contemporary Work ◽  
Microbe Interactions ◽  
Microbial Symbionts ◽  
Host Sponge ◽  
Nutritional Benefits

Marine sponges have been successful in their expansion across diverse ecological niches around the globe. Pioneering work attributed this success to both a well-developed aquiferous system that allowed for efficient filter feeding on suspended organic matter and the presence of microbial symbionts that can supplement host heterotrophic feeding with photosynthate or dissolved organic carbon. We now know that sponge-microbe interactions are host-specific, highly nuanced, and provide diverse nutritional benefits to the host sponge. Despite these advances in the field, many current hypotheses pertaining to the evolution of these interactions are overly generalized; these over-simplifications limit our understanding of the evolutionary processes shaping these symbioses and how they contribute to the ecological success of sponges on modern coral reefs. To highlight the current state of knowledge in this field, we start with seminal papers and review how contemporary work using higher resolution techniques has both complemented and challenged their early hypotheses. We outline different schools of thought by discussing evidence of symbiont contribution to both host ecological divergence and convergence, nutritional specificity and plasticity, and allopatric and sympatric speciation. Based on this synthesis, we conclude that the evolutionary pressures shaping these interactions are complex, with influences from both external (nutrient limitation and competition) and internal (fitness trade-offs and evolutionary constraints) factors. We outline recent controversies pertaining to these evolutionary pressures and place our current understanding of these interactions into a broader ecological and evolutionary framework. Finally, we propose areas for future research that we believe will lead to important new developments in the field.

scholarly journals Comparative Genomics Reveals Ecological and Evolutionary Insights into Sponge-Associated Thaumarchaeota

mSystems ◽  
2019 ◽  
Vol 4 (4) ◽  
Author(s):  
Shan Zhang ◽  
Weizhi Song ◽  
Bernd Wemheuer ◽  
Julie Reveillaud ◽  
Nicole Webster ◽  
...  
Keyword(s):  
Defense Mechanisms ◽  
Marine Sponges ◽  
Metagenomic Data ◽  
Ecological Niches ◽  
Evolutionary Adaptation ◽  
Free Living ◽  
Content Type ◽  
Functional Features ◽  
Metabolic Properties ◽  
Microbial Symbionts

ABSTRACT Thaumarchaeota are frequently reported to associate with marine sponges (phylum Porifera); however, little is known about the features that distinguish them from their free-living thaumarchaeal counterparts. In this study, thaumarchaeal metagenome-assembled genomes (MAGs) were reconstructed from metagenomic data sets derived from the marine sponges Hexadella detritifera, Hexadella cf. detritifera, and Stylissa flabelliformis. Phylogenetic and taxonomic analyses revealed that the three thaumarchaeal MAGs represent two new species within the genus Nitrosopumilus and one novel genus, for which we propose the names “Candidatus UNitrosopumilus hexadellus,” “Candidatus UNitrosopumilus detritiferus,” and “Candidatus UCenporiarchaeum stylissum” (the U superscript indicates that the taxon is uncultured). Comparison of these genomes to data from the Sponge Earth Microbiome Project revealed that “Ca. UCenporiarchaeum stylissum” has been exclusively detected in sponges and can hence be classified as a specialist, while “Ca. UNitrosopumilus detritiferus” and “Ca. UNitrosopumilus hexadellus” are also detected outside the sponge holobiont and likely lead a generalist lifestyle. Comparison of the sponge-associated MAGs to genomes of free-living Thaumarchaeota revealed signatures that indicate functional features of a sponge-associated lifestyle, and these features were related to nutrient transport and metabolism, restriction-modification, defense mechanisms, and host interactions. Each species exhibited distinct functional traits, suggesting that they have reached different stages of evolutionary adaptation and/or occupy distinct ecological niches within their sponge hosts. Our study therefore offers new evolutionary and ecological insights into the symbiosis between sponges and their thaumarchaeal symbionts. IMPORTANCE Sponges represent ecologically important models to understand the evolution of symbiotic interactions of metazoans with microbial symbionts. Thaumarchaeota are commonly found in sponges, but their potential adaptations to a host-associated lifestyle are largely unknown. Here, we present three novel sponge-associated thaumarchaeal species and compare their genomic and predicted functional features with those of closely related free-living counterparts. We found different degrees of specialization of these thaumarchaeal species to the sponge environment that is reflected in their host distribution and their predicted molecular and metabolic properties. Our results indicate that Thaumarchaeota may have reached different stages of evolutionary adaptation in their symbiosis with sponges.

scholarly journals Morphological characterization of virus-like particles in coral reef sponges

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5625 ◽  
Author(s):  
Cecília Pascelli ◽  
Patrick W. Laffy ◽  
Marija Kupresanin ◽  
Timothy Ravasi ◽  
Nicole S. Webster
Keyword(s):  
Morphological Characterization ◽  
Marine Sponges ◽  
Microbial Consortia ◽  
Preparation Methods ◽  
Transmission Electron ◽  
Diverse Communities ◽  
Microbe Interactions ◽  
Microbial Symbionts ◽  
Host Complex

Marine sponges host complex microbial consortia that vary in their abundance, diversity and stability amongst host species. While our understanding of sponge-microbe interactions has dramatically increased over the past decade, little is known about how sponges and their microbial symbionts interact with viruses, the most abundant entities in the ocean. In this study, we employed three transmission electron microscopy (TEM) preparation methods to provide the first comprehensive morphological assessment of sponge-associated viruses. The combined approaches revealed 50 different morphologies of viral-like particles (VLPs) represented across the different sponge species. VLPs were visualized within sponge cells, within the sponge extracellular mesohyl matrix, on the sponge ectoderm and within sponge-associated microbes. Non-enveloped, non-tailed icosahedral VLPs were the most commonly observed morphotypes, although tailed bacteriophage, brick-shaped, geminate and filamentous VLPs were also detected. Visualization of sponge-associated viruses using TEM has confirmed that sponges harbor not only diverse communities of microorganisms but also diverse communities of viruses.

scholarly journals Immune function during pregnancy varies between ecologically distinct populations

2020 ◽  
Vol 2020 (1) ◽  
pp. 114-128
Author(s):  
Carmen Hové ◽  
Benjamin C Trumble ◽  
Amy S Anderson ◽  
Jonathan Stieglitz ◽  
Hillard Kaplan ◽  
...  
Keyword(s):  
Leukocyte Count ◽  
Total Leukocyte Count ◽  
Future Research ◽  
Differential Leukocyte Count ◽  
Ecological Conditions ◽  
Trade Offs ◽  
The Usa ◽  
Immunological Changes ◽  
Fetal Antigens ◽  
Pathogen Exposure

Abstract Background and objectives Among placental mammals, females undergo immunological shifts during pregnancy to accommodate the fetus (i.e. fetal tolerance). Fetal tolerance has primarily been characterized within post-industrial populations experiencing evolutionarily novel conditions (e.g. reduced pathogen exposure), which may shape maternal response to fetal antigens. This study investigates how ecological conditions affect maternal immune status during pregnancy by comparing the direction and magnitude of immunological changes associated with each trimester among the Tsimane (a subsistence population subjected to high pathogen load) and women in the USA. Methodology Data from the Tsimane Health and Life History Project (N = 935) and the National Health and Nutrition Examination Survey (N = 1395) were used to estimate population-specific effects of trimester on differential leukocyte count and C-reactive protein (CRP), a marker of systemic inflammation. Results In both populations, pregnancy was associated with increased neutrophil prevalence, reduced lymphocyte and eosinophil count and elevated CRP. Compared to their US counterparts, pregnant Tsimane women exhibited elevated lymphocyte and eosinophil counts, fewer neutrophils and monocytes and lower CRP. Total leukocyte count remained high and unchanged among pregnant Tsimane women while pregnant US women exhibited substantially elevated counts, resulting in overlapping leukocyte prevalence among all third-trimester individuals. Conclusions and implications Our findings indicate that ecological conditions shape non-pregnant immune baselines and the magnitude of immunological shifts during pregnancy via developmental constraints and current trade-offs. Future research should investigate how such flexibility impacts maternal health and disease susceptibility, particularly the degree to which chronic pathogen exposure might dampen inflammatory response to fetal antigens. Lay Summary This study compares immunological changes associated with pregnancy between the Tsimane (an Amazonian subsistence population) and individuals in the USA. Results suggest that while pregnancy enhances non-specific defenses and dampens both antigen-specific immunity and parasite/allergy response, ecological conditions strongly influence immune baselines and the magnitude of shifts during gestation.

scholarly journals From tree to architecture: how functional morphology of arborescence connects plant biology, evolution and physics

2021 ◽  
Author(s):  
Anita Roth-Nebelsick ◽  
Tatiana Miranda ◽  
Martin Ebner ◽  
Wilfried Konrad ◽  
Christopher Traiser
Keyword(s):  
Land Plant ◽  
Plant Evolution ◽  
Ecological Niches ◽  
Long Distance ◽  
Ongoing Research ◽  
Long Distance Transport ◽  
Theoretical Approaches ◽  
Trade Offs ◽  
Interfacial Physics ◽  
Plant Water Transport

AbstractTrees are the fundamental element of forest ecosystems, made possible by their mechanical qualities and their highly sophisticated conductive tissues. The evolution of trees, and thereby the evolution of forests, were ecologically transformative and affected climate and biogeochemical cycles fundamentally. Trees also offer a substantial amount of ecological niches for other organisms, such as epiphytes, creating a vast amount of habitats. During land plant evolution, a variety of different tree constructions evolved and their constructional principles are a subject of ongoing research. Understanding the “natural construction” of trees benefits strongly from methods and approaches from physics and engineering. Plant water transport is a good example for the ongoing demand for interdisciplinary efforts to unravel form-function relationships on vastly differing scales. Identification of the unique mechanism of water long-distance transport requires a solid basis of interfacial physics and thermodynamics. Studying tree functions by using theoretical approaches is, however, not a one-sided affair: The complex interrelationships between traits, functionality, trade-offs and phylogeny inspire engineers, physicists and architects until today.

Navigating NGO–Government Relations in Human Rights: New Archival Evidence from Amnesty International, 1961–1986

2021 ◽  
Author(s):  
Swati Srivastava
Keyword(s):  
Human Rights ◽  
Oral History ◽  
Social History ◽  
Future Research ◽  
International Institute ◽  
Strategic Choices ◽  
Small Individual ◽  
Amnesty International ◽  
Government Relations ◽  
Trade Offs

Abstract This research note unveils new archival evidence from Amnesty International's first twenty-five years (1961–1986) to shed light on the realization of international human rights as Amnesty balanced “nonpolitical politics” through multifaceted government relations. The research draws from minutes and reports of eighty meetings of Amnesty's executive leadership and interviews from the 1983 to 1985 Amnesty Oral History project, all collected from the International Institute of Social History. The records show that during this time Amnesty relied on government and foundation funding to exit a severe financial crisis. Amnesty also cultivated a private diplomatic network with governments for access and advocacy and conducted side bargains with closed countries for access and reforms. In one sense, the new evidence complicates the conventional wisdom that Amnesty was only financed from small, individual donors and stayed away from private government dealings. In another sense, the new data extend existing insights about INGO strategic action by revealing Amnesty's pragmatic trade-offs when maintaining arms–length relations with governments to better appreciate the organization's early challenges and accomplishments. The note ultimately contributes to scholarship on the strategic choices of INGOs and provides new data for future research on the agency of nonstate actors in global governance navigating complex government relations. Esta nota de investigación presenta nueva evidencia documental de los primeros 25 años de Amnistía Internacional (Amnesty International), de 1961 a 1986, para arrojar luz sobre el cumplimiento de las normas internacionales de derechos humanos mientras Amnistía balanceaba la “política no política” mediante relaciones gubernamentales polifacéticas. La investigación incorpora actas e informes de 80 reuniones del liderazgo ejecutivo de Amnistía y entrevistas de 1983 a 1985 del proyecto Historia Oral de Amnistía (Amnesty Oral History), recopiladas del Instituto Internacional de Historia Social. Los documentos muestran que, en ese momento, Amnistía necesitó financiación gubernamental y de fundaciones para salir de una crisis financiera grave. Amnistía también cultivó una red diplomática privada con gobiernos a cambio de acceso y defensa, y tuvo negocios paralelos con países cerrados a cambio de acceso y reformas. En un sentido, la nueva evidencia complica la sabiduría convencional de que Amnistía solo tuvo financiamiento de donantes pequeños e individuos y se mantuvo lejos de los negocios privados con gobiernos. En contraste, los nuevos datos amplían las percepciones existentes sobre la acción estratégica de organizaciones no gubernamentales internacionales (ONGI), revelando las concesiones pragmáticas de Amnistía al mantener relaciones independientes con gobiernos, y permiten apreciar mejor los desafíos y logros iniciales de la organización. La nota, fundamentalmente, contribuye a la investigación sobre las decisiones estratégicas de las ONGI y brinda nuevos datos para futuras investigaciones sobre la autonomía de los actores no estatales que navegan relaciones gubernamentales complejas en la gobernanza global. Cet exposé de recherche dévoile de nouvelles preuves issues des 25 premières années d'archives d'Amnesty International (1961–1986) pour apporter un éclairage sur l'application des droits de l'Homme tandis qu'Amnesty équilibrait la « politique apolitique » par le biais de relations gouvernementales à plusieurs facettes. Cette recherche s'appuie sur des minutes et rapports de 80 réunions de la haute direction d'Amnesty, ainsi que sur des entretiens qui ont eu lieu entre 1983 et 1985 dans le cadre du projet Oral History (Histoire orale) d'Amnesty. Ces données ont toutes été recueillies auprès de l'Institut International d'Histoire Sociale. Les archives montrent que durant cette période, Amnesty a dû compter sur le financement de gouvernements et de fondations pour sortir d'une grave crise financière. Amnesty a également cultivé un réseau diplomatique privé avec des gouvernements pour faciliter son accès et son plaidoyer dans le pays concerné tout en menant des négociations parallèles avec les pays fermés pour y favoriser son accès et les réformes. En un sens, les nouvelles preuves compliquent les idées reçues selon lesquelles Amnesty ne serait financée que par de petits donateurs individuels et resterait à l’écart des affaires gouvernementales privées. Mais en un autre sens, ces nouvelles données enrichissent les renseignements existants sur l'action stratégique des organisations non gouvernementales internationales en révélant qu'Amnesty s’était livrée à des compromis pragmatiques en entretenant des relations avec les gouvernements tout en restant à distance. Ces renseignements nous permettent donc de mieux apprécier les premiers défis et accomplissements de l'organisation. En définitive, cet exposé contribue aux études sur les choix stratégiques des organisations non gouvernementales internationales et fournit de nouvelles données pour les recherches futures sur l'intervention des acteurs non étatiques dans la gouvernance mondiale tandis qu'ils naviguent dans des relations gouvernementales complexes.

scholarly journals Antimicrobial Activities of Marine Sponge-Associated Bacteria

2021 ◽  
Vol 9 (1) ◽  
pp. 171
Author(s):  
Yitayal S. Anteneh ◽  
Qi Yang ◽  
Melissa H. Brown ◽  
Christopher M. M. Franco
Keyword(s):  
Pathogenic Bacteria ◽  
South Australia ◽  
Multidrug Resistant ◽  
Antimicrobial Activities ◽  
Marine Sponges ◽  
Bioactive Metabolites ◽  
Human Pathogens ◽  
Sponge Associated Bacteria ◽  
Microbial Symbionts ◽  
Bacteria And Fungi

The misuse and overuse of antibiotics have led to the emergence of multidrug-resistant microorganisms, which decreases the chance of treating those infected with existing antibiotics. This resistance calls for the search of new antimicrobials from prolific producers of novel natural products including marine sponges. Many of the novel active compounds reported from sponges have originated from their microbial symbionts. Therefore, this study aims to screen for bioactive metabolites from bacteria isolated from sponges. Twelve sponge samples were collected from South Australian marine environments and grown on seven isolation media under four incubation conditions; a total of 1234 bacterial isolates were obtained. Of these, 169 bacteria were tested in media optimized for production of antimicrobial metabolites and screened against eleven human pathogens. Seventy bacteria were found to be active against at least one test bacterial or fungal pathogen, while 37% of the tested bacteria showed activity against Staphylococcus aureus including methicillin-resistant strains and antifungal activity was produced by 21% the isolates. A potential novel active compound was purified possessing inhibitory activity against S. aureus. Using 16S rRNA, the strain was identified as Streptomyces sp. Our study highlights that the marine sponges of South Australia are a rich source of abundant and diverse bacteria producing metabolites with antimicrobial activities against human pathogenic bacteria and fungi.

scholarly journals Characterization of the skin microbiota in bullous pemphigoid patients and controls reveals novel microbial indicators of disease

2021 ◽  
Author(s):  
Meriem Belheouane ◽  
Britt M Hermes ◽  
Nina Van Beek ◽  
Sandrine Benoit ◽  
Philippe Bernard ◽  
...  
Keyword(s):  
Bullous Pemphigoid ◽  
Disease Risk ◽  
Disease Status ◽  
The Elderly ◽  
Future Research ◽  
Sampling Effort ◽  
Skin Microbiota ◽  
Important Indicator ◽  
Blistering Disease ◽  
Microbe Interactions

Bullous pemphigoid (BP) is an autoimmune skin blistering disease afflicting mostly the elderly and is associated with significantly increased mortality. Here, we conducted the most extensive sampling effort of skin microbiota in BP to date to analyze whether intra-individual, body-site-specific, and/or geographical variation contributes to the emergence of BP. We find marked differences in the skin microbiota of BP patients compared to that of control subjects, and moreover that disease status rather than skin biogeography governs the skin microbiota composition in BP. Our data reveal a discernible transitional stage between normal and diseased skin in BP characterized by a loss of protective microbiota and an increase in sequences matching Staphylococcus aureus, a known inflammation-promoting species. Notably, S. aureus is ubiquitously associated with disease status, suggesting that this taxon is an important indicator of BP. Importantly, differences in a few key indicator taxa are able to reliably discriminate between BP patients and controls, characterized by their opposing abundance patterns. This may serve as valuable information for assessing disease risk and treatment outcomes. Future research will focus on the functional analysis of host-microbe and microbe-microbe interactions and the relevance of the host genome for microbiota abundances to identify novel BP treatment approaches.

Attitudes and behaviour towards organic products: an exploratory study

2008 ◽  
Vol 36 (2) ◽  
pp. 158-175 ◽  
Author(s):  
Efthimia Tsakiridou ◽  
Christina Boutsouki ◽  
Yorgos Zotos ◽  
Kostantinos Mattas
Keyword(s):  
Organic Food ◽  
Food Products ◽  
Local Economy ◽  
Health Concern ◽  
Future Research ◽  
Consumer Decision Making ◽  
Content Type ◽  
Actual Behaviour ◽  
Trade Offs ◽  
Organic Products

PurposeThe aim of this paper is to identify consumers' attitudes and behaviour towards organic products in Greece.Design/methodology/approachThis paper draws on a non‐probability quota sample of 660 respondents to explore the attitudes and behaviour of Greek consumers towards organic food products.FindingsGreek consumers seem to be informed about environmental and health issues. They seek information about the nutritional value of food and demand more products free from chemical residues. The results show that most consumers associate organic consumption mainly with fruit and vegetables. Although demographics seem to affect attitudes towards organics, their value in explaining actual behaviour is minimal.Research limitations/implicationsIt is recognized that the data gathered in this study focus on the metropolitan area of Thessaloniki, Greece. The specific area though, is considered to be representative of the total Greek population. The results confirm that health, concern for the environment, animal welfare and support of the local economy are drivers of organic consumption. However, there is an indication that the importance of motives and barriers may vary for different product categories and perhaps future research should focus on product segmentation.Practical implicationsAlthough certain similarities in consumers' attitudes towards organic food products have been identified, this paper records the variation in behaviour towards organics among the various consumer groups examined in Greece, and highlights the gap between attitudes and actual behaviour. Given the complexity of consumer decision making, future research should explore the other value trade‐offs that consumers make.Originality/valueThis paper attempts to provide evidence on the relatively under researched area of organics attitudes and behaviour in Greece.

A systematic review of the literature on supply chain agility

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Bharat Singh Patel ◽  
Murali Sambasivan
Keyword(s):  
Supply Chain ◽  
Cost Benefit ◽  
Business Environment ◽  
Future Research ◽  
Research Directions ◽  
Content Type ◽  
Trade Offs ◽  
Supply Chain Agility ◽  
Agility Assessment ◽  
Future Research Directions

Purpose The purpose of this study is to critically examine the scholarly articles associated Murali Sambasivan with the diverse aspects of supply chain agility (SCA). The review highlights research insights, existing gaps and future research directions that can help academicians and practitioners gain a comprehensive understanding of SCA. Design/methodology/approach The present study has adopted author co-citation analysis as the research methodology, with a view to thoroughly investigating the good-quality articles related to SCA that have been published over a period of 22 years (1999-2020). In this study, 126 research papers on SCA – featuring diverse aspects of agility – from various reputed journals have been examined, analysed and assimilated. Findings The salient findings of this research are, namely, agility is different from other similar concepts, such as flexibility, leanness, adaptability and resilience; of the 13 dimensions of agility discussed in the literature, the prominent ones are quickness, responsiveness, competency and flexibility; literature related to SCA can be categorised as related to modelling the enablers, agility assessment, agility implementation, leagility and agility maximisation. This research proposes a more practical definition and framework for SCA. The probable areas for future research are, namely, impediments to agility, effective approaches to agility assessment, cost-benefit trade-offs to be considered whilst implementing agility, empirical research to validate the framework and SCA in the domain of healthcare and disaster relief supply chains. Practical implications This paper provides substantial insights to practitioners who primarily focus on measuring and implementing agility in the supply chain. The findings of this study will help the supply chain manager gain a better idea about how to become competitive in today’s dynamic and turbulent business environment. Originality/value The originality of this study is in: comprehensively identifying the various issues related to SCA, such as related concepts, definitions, dimensions and different categories of studies covered in literature, proposing a new definition and framework for SCA and identifying potential areas for future research, to provide deeper insights into the subject and highlight areas for future research.

WHY DO INSECTS EVOLVE IMMUNE PRIMING? A SEARCH FOR CROSSROADS

2021 ◽  
Author(s):  
Arun Prakash ◽  
imroze khan
Keyword(s):  
Immune Responses ◽  
Low Dose ◽  
Immune Memory ◽  
Comparative Approach ◽  
Future Research ◽  
Subsequent Infection ◽  
Immune Priming ◽  
Trade Offs ◽  
Evolutionary Response ◽  
Basal Immunity

Until recently, it was assumed that insects lack immune memory since they do not have vertebrate-like specialized memory cells. Therefore, their most well studied evolutionary response against pathogens was increased basal immunity. However, growing evidence suggests that many insects also exhibit a form of immune memory (immune priming), where prior exposure to a low dose of infection confers protection against subsequent infection by the same pathogen that acts both within and across generations. Most strikingly, they can rapidly evolve as a highly parallel and mutually exclusive strategy from basal immunity, under different selective conditions and with divergent evolutionary trade-offs. However, the relative importance of priming as an optimal immune strategy also has contradictions, primarily because supporting mechanisms are still unclear. In this review, we adopt a comparative approach to highlight several emerging evolutionary, ecological and mechanistic features of priming vs basal immune responses that warrant immediate attention for future research.

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