Adapting with Microbial Help: Microbiome Flexibility Facilitates Rapid Responses to Environmental Change

Abstract

Animals and plants are metaorganisms and associate with microbes that affect their physiology, stress tolerance, and fitness. Here the hypothesis that alteration of the microbiome may constitute a fast‐response mechanism to environmental change is examined. This is supported by recent reciprocal transplant experiments with reef corals, which have shown that their microbiome adapts to thermally variable habitats and changes over time when transplanted into different environments. Further, inoculation of corals with beneficial bacteria increases their stress tolerance. But corals differ in their ability to flexibly associate with different bacteria. How scales of microbiome flexibility may reflect different metaorganism adaptation mechanisms is discussed and future directions for research are pinpointed. It is posited that microbiome flexibility is a broad phenomenon that contributes to the ability of organisms to respond to environmental change. Importantly, adapting with microbial help may provide an alternate route to organismal adaptation that facilitates rapid responses.

Coral-Associated Viral Assemblages From the Central Red Sea Align With Host Species and Contribute to Holobiont Genetic Diversity

“…Corals also offer persistent, protected, and nutrient-rich microenvironments to anchor stable partnerships with a wide diversity of microbes. Single-celled dinoflagellates of the family Symbiodiniaceae provide energy for corals to build massive three-dimensional calcium carbonate skeletons ( Muscatine et al, 1981 ; Burriesci et al, 2012 ), while some bacteria presumably contribute to metabolic cycling and may be involved in immunity and environmental adaptation ( Raina et al, 2009 ; Ziegler et al, 2017 ; Robbins et al, 2019 ; Voolstra and Ziegler, 2020 ). While coral-associated bacterial and Symbiodiniaceae communities have been extensively studied, viral diversity and function have only recently been explored (for an overview consult the following reviews: van Oppen et al, 2009 ; Vega Thurber and Correa, 2011 ; Sweet and Bythell, 2017 ; Vega Thurber et al, 2017 ).…”

Insights into the cultured bacterial fraction of corals

“…Similarly, growing evidence underlines the key role compounds produced by bacteria have on host health 42,43,29,44,45 . For instance, 46 was among the first to demonstrate that mucusassociated bacteria from healthy colonies inhibit the growth of potential pathogens, like the vibrios mentioned above.…”

Horizontal gene transfer-mediated bacterial strain variation affects host fitness

“…Because the result of HGT here provides a potential benefit to the host under thiamine poor conditions that are often encountered under natural conditions e.g. on thiamine poor fruit, our study contributes to a broader view of adaptation that can involve a flexible microbiome [4,100].…”