Cooperative Symbiosis Research Articles

Vertical distribution of arsenic and bacterial communities in calcareous farmland amending by organic fertilizer and iron-oxidizing bacteria: Field experiment on concomitant remediation

The migration and transformation mechanisms of arsenic (As) in soil environments necessitate an understanding of its influencing processes. Here, we investigate the subsurface biogeochemical transformation of As and iron (Fe) through amended in the top 20 cm with iron oxidizing bacteria (FeOB) and organic fertilizer (OF). Our comprehensive 400-day field study, conducted in a calcareous soil profile sectioned into 20 cm increments, involved analysis by sequential extraction and assessment of microbial properties. The results reveal that the introduction of additional OF increased the release ratio of As/Fe from the non-specific adsorption fraction (136.47 %) at the subsoil depth (40–60 cm), underscoring the importance of sampling at various depths and time points to accurately elucidate the form, instability, and migration of As within the profile. Examination of bacterial interaction networks indicated a disrupted initial niche in the bottom layer, resulting in a novel cooperative symbiosis. While the addition of FeOB did not lead to the dominance of specific bacterial species, it did enhance the relative abundance of As-tolerant Acidobacteria and Gemmatimonadetes in both surface (39.2 % and 38.76 %) and deeper soils (44.29 % and 23.73 %) compared to the control. Consequently, the amendment of FeOB in conjunction with OF facilitated the formation of poorly amorphous Fe (hydr)oxides in the soil, achieved through abiotic and biotic sequestration processes. Throughout the long-term remediation process, the migration coefficient of bioavailable As within the soil profile decreased, indicating that these practices did not exacerbate As mobilization. This study carries significant implications for enhancing biogeochemical cycling in As-contaminated Sierozem soils and exploring potential bioremediation strategies. Environmental implicationThe long-term exposure of sewage irrigation has potential adverse effects on the local ecosystem, causing serious environmental problems. Microorganisms play a vital role in the migration and transformation of arsenic in calcareous soil in arid areas, which highlights the necessity of understanding its dynamics. The vertical distribution, microbial community and fate of arsenic in calcareous farmland soil profile in northwest China were studied through field experiments. The results of this work have certain significance for the remediation of arsenic-contaminated soil in arid areas, and provide new insights for the migration, transformation and remediation of arsenic in this kind of soil.

Digital Operational Strategies in The Post-Pandemic Era for Travel Companies: A Case Study of Ctrip

The epidemic’s impact has caused the tourism industry to face major challenges and changes in the post-epidemic era, in which the digital operation model has become the key to driving recovery and innovation. Taking Ctrip as an example, this study provides an in-depth analysis of the changes in the digital operation mode of tourism enterprises in the post-epidemic era. Firstly, the context and situation of Ctrip’s activities have changed in the digital environment, expanding the online business space and strengthening the interaction between the company and consumers. Second, the digital environment has changed corporate and consumer behavior from competition to cooperative symbiosis while triggering the socialization and personalization of consumer behavior. In addition, Ctrip’s travel products have changed in the digital environment, with data analysis to tailor travel products for consumers. Practical applications of Ctrip’s digital operations, including user demand forecasting and product design optimization, are further discussed. It is concluded that digital operations are important in improving management efficiency, meeting consumer demand, pricing strategy, and risk control. However, digital operations face legal, protection, and risk issues that require further research and solutions. This study provides useful experiences and insights for developing digital operation modes in tourism enterprises.

Microalgal Consortia for Waste Treatment and Valuable Bioproducts

Microalgae have been considered a promising and sustainable candidate for wastewater treatment and valuable bioproducts, such as feedstocks for food, nutrients, and energy. However, many challenging bottlenecks, such as low biomass productivity, expensive biomass harvesting techniques, and inefficient extraction of biofuels restrict its large-scale commercial production. Symbiotic relationships between microalgae and bacteria, also known as microalgal consortia, have proven to be effective solutions for mitigating technical and economic limitations. The natural and artificial symbiotic microalgal consortia combine microorganisms with various metabolic activities, which leads to valuable biomass production and the removal of nutrients, pharmaceuticals, and personal care products (PPCP) from wastewater. Many microalgal consortia have been applied for various wastewater treatments with reduced energy costs and higher efficiency in recovering valuable resources. In this study we review the present research status and prospects of microalgal consortia, emphasizing the associated mechanism of microalgae consortia cooperative symbiosis and its studies on diverse environmental and biotechnological applications.

Evolutionary Path and Sustainable Optimization of an Innovation Ecosystem for a High-Tech Enterprise Based on Empirical Evidence from Hubei Province

This study focuses on the evolutionary path and sustainable optimization of an innovation ecosystem for a high-tech enterprise. To analyze the formation and structure of such an ecosystem, this study applies the Lotka–Volterra model to argue that cooperative symbiosis is an effective path for system evolution. It establishes a system dynamics model to analyze the system feedback mechanism and takes the development of an innovation ecosystem for a high-tech enterprise in Hubei Province as an example to discuss the dynamic factors that affect the system’s evolution and to design the sustainable optimization path of the system. The empirical results show that the system’s innovation input can only promote the positive effects of system evolution to a certain extent, and that regulatory elements such as policies and infrastructure can impact governance effectiveness and promote system optimization and sustainable development.

A multiproducer microbiome generates chemical diversity in the marine sponge Mycale hentscheli

Bacterial specialized metabolites are increasingly recognized as important factors in animal-microbiome interactions: for example, by providing the host with chemical defenses. Even in chemically rich animals, such compounds have been found to originate from individual members of more diverse microbiomes. Here, we identified a remarkable case of a moderately complex microbiome in the sponge host Mycale hentscheli in which multiple symbionts jointly generate chemical diversity. In addition to bacterial pathways for three distinct polyketide families comprising microtubule-inhibiting peloruside drug candidates, mycalamide-type contact poisons, and the eukaryotic translation-inhibiting pateamines, we identified extensive biosynthetic potential distributed among a broad phylogenetic range of bacteria. Biochemical data on one of the orphan pathways suggest a previously unknown member of the rare polytheonamide-type cytotoxin family as its product. Other than supporting a scenario of cooperative symbiosis based on bacterial metabolites, the data provide a rationale for the chemical variability of M. hentscheli and could pave the way toward biotechnological peloruside production. Most bacterial lineages in the compositionally unusual sponge microbiome were not known to synthesize bioactive metabolites, supporting the concept that microbial dark matter harbors diverse producer taxa with as yet unrecognized drug discovery potential.

Symbiont-Derived Antimicrobials Contribute to the Control of the Lepidopteran Gut Microbiota

Insects develop efficient antimicrobial strategies to flourish in a bacterial world. It has long been proposed that native gut microbiota is an important component of host defense; however, the responsible species have rarely been isolated to elucidate the mechanism of action. Here we show that the dominant symbiotic bacterium Enterococcus mundtii associated with the generalist herbivore Spodoptera littoralis actively secretes a stable class IIa bacteriocin (mundticin KS) against invading bacteria, but not against other gut residents, facilitating the normal development of host gut microbiota. A mundticin-defective strain lost inhibitory activity. Furthermore, purified mundticin cures infected larvae. Thus, the constitutively produced antimicrobials by native extracellular symbionts create a significant chemical barrier inside limiting invader expansion. This unique property also benefits E.mundtii itself by providing a competitive advantage, contributing to its dominance within complex microbial settings and its prevalence across Lepidoptera, and probablypromotes the long-term cooperative symbiosis between both parties.

A novel aspect of goby–shrimp symbiosis: gobies provide droppings in their burrows as vital food for their partner shrimps

The goby–shrimp symbiosis is a well-known example of mutualism among marine animals. It is generally accepted that the shrimp provides a sheltering burrow for the partner goby, and the goby warns its host about predatory risk. Other types of benefits between the participants are proposed, but most are based on anecdotal evidence. We propose the hypothesis that shrimps consume the gobies’ droppings inside the burrow as their primary food source, based on preliminary field observations wherein gobies were never observed to defecate outside burrows despite frequent foraging, and partner shrimps were seldom observed eating outside burrows. We tested this hypothesis with a laboratory experiment conducted over a period of 2 weeks using the host shrimp Alpheus bellulus and its partner goby Amblyeleotris japonica. Our results were consistent with our predictions: (i) when a shrimp and a goby were kept together in a tank and only the goby was provided with food, the shrimp’s body weight was maintained. (ii) When a shrimp was kept alone in a tank and was provided with the faeces of a goby kept in a different tank, the shrimp’s body weight decreased slightly but was not significantly different from that of the shrimp in treatment (i). By contrast, when a shrimp was kept alone in a tank and given no food as control treatment, its body weight decreased much more than that of shrimps in the two treatments. These results together with field observations support the hypothesis that gobies provide faeces as a vital food source for shrimps; this is a novel finding in the study of this goby in their cooperative symbiosis. We suggest this food provisioning by goby for partner shrimp will be common in the shrimp–goby symbioses in coral reefs.

Gastrointestinal Tract Commensal Bacteria and Probiotics: Influence on End-Organ Physiology.

Bacteria represent the earliest form of independent life on this planet. Bacterial development has included cooperative symbiosis with plants (e.g., Leguminosae family and nitrogen fixing bacteria in soil) and animals (e.g., the gut microbiome). It is generally agreed upon that the fusion of two prokaryotes evolutionarily gave rise to the eukaryotic cell in which mitochondria may be envisaged as a genetically functional mosaic, a relic from one of the prokaryotes. This is expressed by the appearance of mitochondria in eukaryotic cells (an alpha-proteobacteria input), a significant endosymbiotic evolutionary event. As such, the evolution of human life has been complexly connected to bacterial activities. Hence, microbial colonization of mammals has been a progressively driven process. The interactions between the human host and the microbiome inhabiting the gastrointestinal tract (GIT) for example, afford the human host the necessary cues for the development of regulated signals that in part are induced by reactive oxygen species (ROS). This regulated activity then promotes immunological tolerance and metabolic regulation and stability, which then helps establish control of local and extraintestinal end-organ (e.g., kidneys) physiology. Pharmacobiotics, the targeted administration of live probiotic cultures, is an advancing area of potential therapeutics, either directly or as adjuvants. Hence the continued scientific understanding of the human microbiome in health and disease may further lead to fine tuning the targeted delivery of probiotics for a therapeutic gain.

Live probiotic cultures and the gastrointestinal tract: symbiotic preservation of tolerance whilst attenuating pathogenicity.

Bacteria comprise the earliest form of independent life on this planet. Bacterial development has included co-operative symbiosis with plants (e.g., Leguminosae family and nitrogen fixing bacteria in soil) and animals (e.g., the gut microbiome). A fusion event of two prokaryotes evolutionarily gave rise to the eukaryote cell in which mitochondria may be envisaged as a genetically functional mosaic, a relic from one of the prokaryote cells. The discovery of bacterial inhibitors such chloramphenicol and others has been exploited to highlight mitochondria as arising from a bacterial progenitor. As such the evolution of human life has been complexly connected to bacterial activity. This is embodied, by the appearance of mitochondria in eukaryotes (alphaproteobacteria contribution), a significant endosymbiotic evolutionary event. During the twentieth century there was an increasing dependency on anti-microbials as mainline therapy against bacterial infections. It is only comparatively recently that the essential roles played by the gastrointestinal tract (GIT) microbiome in animal health and development has been recognized as opposed to the GIT microbiome being a toxic collection of micro-organisms. It is now well-documented that the GIT microbiome is comprised of a complex cohort of commensal and potentially pathogenic bacteria. Microbial interactions in the GIT provide the necessary cues for the development of regulated signals [in part by reactive oxygen species (ROS)] that promote immunological tolerance, metabolic regulation and stability, and other factors, which may then help control local and extra-intestinal end organ (e.g., kidneys) physiology. Pharmacobiotics, the administration of live probiotic cultures is an exciting growth area of potential therapeutics, developing together with an increased scientific understanding of GIT microbiome symbiosis in health and disease. Hence probiotic bacteria may provide a therapeutic connect with the GIT microbiome that can rescue mitochondrial dysfunction by linking a biologically plausible cellular signaling program (ROS reliant) between the human host and its microbiome cohort for a continued co-operative symbiosis that maintains homeostasis favorable to both.

The Motivation of Minor Enterprises Competition, Cooperation and Symbiosis

The competition and symbiosis relation of minor enterprises results from their active participation and other factors. The main motivations of their symbiotic development are to integrate different resources of relavant enterprises, share benefits and risks, promote continuely rapid development. In network economy era, cooperative symbiosis is playing an important parts in enterprise strategic management and innovation.

Interference competition and high temperatures reduce the virulence of fig wasps and stabilize a fig-wasp mutualism.

Fig trees are pollinated by fig wasps, which also oviposit in female flowers. The wasp larvae gall and eat developing seeds. Although fig trees benefit from allowing wasps to oviposit, because the wasp offspring disperse pollen, figs must prevent wasps from ovipositing in all flowers, or seed production would cease, and the mutualism would go extinct. In Ficus racemosa, we find that syconia (‘figs’) that have few foundresses (ovipositing wasps) are underexploited in the summer (few seeds, few galls, many empty ovules) and are overexploited in the winter (few seeds, many galls, few empty ovules). Conversely, syconia with many foundresses produce intermediate numbers of galls and seeds, regardless of season. We use experiments to explain these patterns, and thus, to explain how this mutualism is maintained. In the hot summer, wasps suffer short lifespans and therefore fail to oviposit in many flowers. In contrast, cooler temperatures in the winter permit longer wasp lifespans, which in turn allows most flowers to be exploited by the wasps. However, even in winter, only in syconia that happen to have few foundresses are most flowers turned into galls. In syconia with higher numbers of foundresses, interference competition reduces foundress lifespans, which reduces the proportion of flowers that are galled. We further show that syconia encourage the entry of multiple foundresses by delaying ostiole closure. Taken together, these factors allow fig trees to reduce galling in the wasp-benign winter and boost galling (and pollination) in the wasp-stressing summer. Interference competition has been shown to reduce virulence in pathogenic bacteria. Our results show that interference also maintains cooperation in a classic, cooperative symbiosis, thus linking theories of virulence and mutualism. More generally, our results reveal how frequency-dependent population regulation can occur in the fig-wasp mutualism, and how a host species can ‘set the rules of the game’ to ensure mutualistic behavior in its symbionts.

The Origin of Synergistic Symbiosis

A dominant theme in the history of life has been the evolutionary innovations of cooperative symbioses: the first genomes near the origin of life, integrated prokaryotic cells, the complex symbiotic communities that evolved into modern eukaryotic cells, lichens, mycorrhizae, and so on. In this paper, a mode l of cooperative symbiosis that shows a threshold condition for the evolution of cooperation is analyzed. The threshold is not easily passed, but cooperative evolution proceeds rapidly once a symbiosis overcomes the threshold. In the model presented here, each species has genetic variability for a symbiotic trait. The trait imposes a reproductive cost on its bearer but enhances the reproduction of its partner species. For example, in the origin of genetic systems, the trait may cause biochemical synergism for the rate of replication of primitive RNA strands as in Eigen and Schuster's hypercycle model. Models of growth are contrasted with synergism, which are most appropriate for the evolution of genetic systems and for mutualisms such as lichens, with the strategic and psychological applications of the Prisoner's Dilemma model.

An essay on psychotherapy and religion

Cultural innovation by thinkers of the early twentieth century created an intellectual impasse between competing understandings of religion. Religion was understood as either transcendence and the sacred (e.g., Otto) or as fantasy and projection (e.g., Freud). Whether a cooperative symbiosis of these orientations toward religion can be achieved is the central and unresolved issue of this paper. "Examined experience" is considered within religious studies and psychotherapy. Although not conclusive, the argument is that examined experience is a means by which the desired symbiosis can be achieved. The essay is personal in that it reflects the author's struggle for understanding, especially as Western (e.g., Christian) and Eastern (e.g., Zen) experiences are examined.