Abstract
Many organisms team up with microbes for defense against predators, parasites, parasitoids, or pathogens. Here we review the described protective symbioses between animals (including marine invertebrates, nematodes, insects, and vertebrates) and bacteria, fungi, and dinoflagellates. We focus on associations where the microbial natural products mediating the protective activity have been elucidated or at least strong evidence for the role of symbiotic microbes in defense is available. In addition to providing an overview of the known defensive animal-microbe symbioses, we aim to derive general patterns on the chemistry, ecology, and evolution of such associations.
Highlights
Defensive animal–microbe symbioses Marine invertebrates Sponges Cnidarians Bryozoans Nemerteans Mollusks Crustaceans Tunicates Terrestrial invertebrates Entomopathogenic nematodes Insects Vertebrates Ecological and evolutionary implications Implications of host ecology and lifestyle Diversity of defensive symbionts and protective chemicals Implications of symbiont localization Evolutionary dynamics Outlook: current status, challenges and opportunities of defensive symbiosis research Acknowledgements References
While symbiosis research has traditionally focused on the nutritional aspects of mutualistic associations between animals and microorganisms, more recent research has revealed the importance of defensive alliances with microorganisms for their hosts' ecology and evolution.[5,6]
We aim to provide an overview of the known defensive symbioses between Metazoa and microorganisms, with an emphasis on associations where host protection is mediated by symbiont-produced secondary metabolites
Summary
All organisms are threatened by antagonistic encounters with predators, pathogens, parasites, and/or parasitoids, which exert strong selective pressures on evolving efficient defense strategies. We are building on previous reviews of microbial protective symbioses in particular groups of animals, including marine organisms,[11,12,13,14] insects,[15,16,17,18,19] and nematodes,[20,21,22] as well as on reviews covering the metabolites produced by symbiotic bacteria.[9,10] Generally, we focus on symbioses for which the defensive chemistry has been elucidated, and a protective bene t for the host has been demonstrated or is at least very likely Most of these involve associations with bacteria, but a few defensive alliances with fungi and dino agellates have been described. His research focuses on the evolution, chemical and molecular ecology of insect–microbe symbioses, with a special interest in defensive alliances
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
