The mutualistic relationship between corals and their unicellular dinoflagellate symbionts (Symbiodinium sp.) is a fundamental component within the ecology of coral reefs. Thermal stress causes the breakdown of the relationship between corals and their symbionts (bleaching). As with other organisms, this symbiosis may acclimate to changes in the environment, thereby potentially modifying the en...

The bacterial endosymbionts of two species of the bivalve genus Solemya from the Pacific Ocean, Solemya terraeregina and Solemya pusilla, were characterized. Prokaryotic cells resembling gram-negative bacteria were observed in the gills of both host species by transmission electron microscopy. The ultrastructure of the symbiosis in both host species is remarkably similar to that of all previous...

Our intestine is the site of an extraordinarily complex and dynamic environmentally transmitted consortial symbiosis. The molecular foundations of beneficial symbiotic host-bacterial relationships in the gut are being revealed in part from studies of simplified models of this ecosystem, where germ-free mice are colonized with specified members of the microbial community, and in part from compar...

Citation: Scheufen T, Iglesias-Prieto R and Enríquez S (2017) Changes in the Number of Symbionts and Symbiodinium Cell Pigmentation Modulate Differentially Coral Light Absorption and Photosynthetic Performance. Front. Mar. Sci. 4:309. doi: 10.3389/fmars.2017.00309 Changes in the Number of Symbionts and Symbiodinium Cell Pigmentation Modulate Differentially Coral Light Absorption and Photosynthe...

Symbiotic microorganisms are extremely widespread in nature, having intimate and often obligatory associations with their`host' species. Despite the near ubiquity of arthropod symbionts, their study has been constrained by their fastidious nature and inability to be cultured out of the arthropod host. Recent advances in molecular biology have provided new tools for symbiosis research and stimul...

Symbionts in each generation are transmitted to new host individuals either vertically (parent to offspring), horizontally (from exogenous sources), or a combination of both. Scleractinian corals make an excellent study system for understanding patterns of symbiont transmission since they harbor diverse symbionts and possess distinct reproductive modes of either internal brooding or external br...

Certain species of Chlorella live within the digestive cells of the fresh water cnidarian Hydra viridis. When introduced into the hydra gut, these symbiotic algae are phagocytized by digestive cells but avoid host digestion and persist at relatively constant numbers within host cells. In contrast, heat-killed symbionts are rapidly degraded after phagocytosis. Live symbionts appear to persist be...

S ymbiosis is the intimate “living together” of different organisms (1), and symbiotic relationships range from mutually beneficial to neutral or parasitic. Indeed, many microbial–host symbioses can vary between these states, depending upon circumstances. Recent years have seen an explosion of discoveries revealing novel microbial–host relationships and interactions. In addition to “classic” nu...

Mutualists and pathogens, collectively called symbionts, are ubiquitous in plant communities. While some symbionts are highly host-specific, others associate with multiple hosts. The outcomes of mul-tispecies host-symbiont interactions with different degrees of speci-ficity are difficult to predict at this point due to a lack of a general conceptual framework. Complicating our predictive power ...