Partner Switching and Metabolic Carbon Flux under Thermal Stress in the Cnidarian-Dinoflagellate Symbiosis DOI Creative Commons

Evan M. Heit

Published: Sept. 18, 2023

<p><strong>Reef corals depend heavily on their symbiotic relationship with dinoflagellates of the family Symbiodiniaceae, which are primary source metabolic energy and hence allow them to survive in oligotrophic tropical seas. The between these two partners is exceptionally sensitive environmental change, however, global warming known induce dysbiosis (i.e., breakdown symbiosis) a process referred as ‘coral bleaching’. adaptive bleaching hypothesis posits that host may acquire new dominant Symbiodiniaceae species after event, either from shift relative abundance resident symbionts (‘shuffling’) or uptake environment (‘switching’), better equipping holobiont whole for regime. However, different symbiont types have nutritional implications coral, potentially limiting potential partner shuffling switching. Energy-rich carbon compounds primarily provided by coral glucose, glycerol, lipids. Yet, it poorly understood how climate change impacts this translocation identity influences response. This thesis, therefore, addressed topic, using sea anemone Exaiptasia diaphana (‘Aiptasia’), globally adopted model system study cnidarian-dinoflagellate symbiosis.</strong></p><p>First, I aimed quantify compare pools carbon-based metabolites under thermal stress symbiont, focusing total carbohydrates (Chapter 2). It was hypothesized (33 °C) would cause decline various metabolites, likely due decreased photosynthetic function host, combined elevated catabolism stress. Metabolites were measured range commercially available metabolite-specific assay kits. As predicted, at high temperature, glucose glycerol remained constant even increased controls. latter observation consistent gluconeogenesis synthesis likes glycerol) response demands temperatures. other hand, use metabolite an osmolyte moderator cellular While test-kit approach used here associated considerable amount inter-sample variability, nevertheless confirmed added previous observations gained much more expensive, technically complex metabolomics methods.</p><p>I then compared photosynthates Aiptasia low, control, temperature (15, 25, 33 oC), when colonized Breviolum minutum, only through Indo-Pacific region (the here), Durusdinium trenchii psygmophilum 3). D. thermally tolerant but opportunistic not typically Aiptasia, while often temperate sub-tropical species, including western Atlantic Ocean. B. minutum translocate photosynthate its control out-perform low temperatures, respectively. To test this, radiotracer (NaH14CO3) measure fixation translocation. Contrary expectations, anemones hosting bleached completely both population density controls, containing did bleach extensively those confirming reputation former ‘thermal generalist.’ With respect metabolism, performed similarly slightly out-performed across all though most benefit temperature. had major influence flux lessening impact bleaching. Specifically, facilitated proportionally higher rates symbiont-cell specific photosynthesis translocation, presumably reduced competition CO2, such heat-stressed continued receive similar amounts controls.</p><p>In summary, thesis demonstrates type metabolism symbiosis. Most interestingly, my findings highlight importance research processes underlie physiology generalists aid adaptation reef natural development tools conservation.</p>

Language: Английский

Microbial-Based Therapies to Restore and Rehabilitate Disrupted Coral Health DOI
Melanie Dörr, Adam R. Barno, Helena D. M. Villela

et al.

Coral reefs of the world, Journal Year: 2025, Volume and Issue: unknown, P. 181 - 195

Published: Jan. 1, 2025

Language: Английский

Citations

2
Horizon scanning the application of probiotics for wildlife DOI Creative Commons
Neus Garcías-Bonet, Anna Roik, Braden Tierney

et al.

Trends in Microbiology, Journal Year: 2023, Volume and Issue: 32(3), P. 252 - 269

Published: Sept. 25, 2023

The provision of probiotics benefits the health a wide range organisms, from humans to animals and plants. Probiotics can enhance stress resilience endangered many which are critically threatened by anthropogenic impacts. use so-called 'probiotics for wildlife' is nascent application, field needs reflect on standards its development, testing, validation, risk assessment, deployment. Here, we identify main challenges this emerging intervention provide roadmap validate effectiveness wildlife probiotics. We cover essential inert negative controls in trials investigation probiotic mechanisms action. also suggest alternative microbial therapies that could be tested parallel with application. Our recommendations align approaches used humans, aquaculture, plants concept wildlife.

Language: Английский

Citations

39
Microbiome Stability Is Linked to Acropora Coral Thermotolerance in Northwestern Philippines DOI Open Access
Jake Ivan Baquiran, John Bennedick Quijano, Madeleine J. H. van Oppen

et al.

Environmental Microbiology, Journal Year: 2025, Volume and Issue: 27(2)

Published: Jan. 31, 2025

Corals associate with a diverse community of prokaryotic symbionts that provide nutrition, antioxidants and other protective compounds to their host. However, the influence microbes on coral thermotolerance remains understudied. Here, we examined microbial communities associated colonies Acropora cf. tenuis exhibit high or low upon exposure 33°C (heated) relative 29°C (control). Using 16S rRNA sequencing, show structure all A. was similar each at control temperature. Thermotolerant colonies, however, had relatively greater abundance Endozoicomonas, Arcobacter, Bifidobacterium Lactobacillus. At elevated temperature, only thermosensitive showed distinct shift in microbiome, an increase Flavobacteriales, Rhodobacteraceae Vibrio, accompanying marked bleaching response. Functional prediction indicated thermotolerant corals were enriched for genes related metabolism, while microbiomes cell motility antibiotic compound synthesis. These differences may contribute variable performance under thermal stress. Identification taxa correlated provides insights into beneficial bacterial groups could be used microbiome engineering support reef health changing climate.

Language: Английский

Citations

1
Genomic exploration of coral-associated bacteria: identifying probiotic candidates to increase coral bleaching resilience in Galaxea fascicularis DOI Creative Commons
Talisa Doering, Kshitij Tandon, Sanjida H. Topa

et al.

Microbiome, Journal Year: 2023, Volume and Issue: 11(1)

Published: Aug. 19, 2023

Reef-building corals are acutely threatened by ocean warming, calling for active interventions to reduce coral bleaching and mortality. Corals associate with a wide diversity of bacteria which can influence health, but knowledge specific functions that may be beneficial under thermal stress is scant. Under the oxidative theory bleaching, scavenge reactive oxygen (ROS) or nitrogen species (RNS) expected enhance resilience. Further, bacterial carbon export might substitute supply from algal photosymbionts, resilience facilitate recovery. To identify probiotic candidates, we sequenced genomes 82 pure-cultured were isolated emerging model Galaxea fascicularis.Genomic analyses showed isolates affiliated 37 genera. Isolates such as Ruegeria, Muricauda Roseovarius found encode genes synthesis antioxidants mannitol, glutathione, dimethylsulfide, dimethylsulfoniopropionate, zeaxanthin and/or β-carotene. Genes involved in RNS-scavenging many G. fascicularis-associated bacteria, represents novel finding several genera (including Pseudophaeobacter). Transporters suggested (semiSWEET) detected seven isolates, including Pseudovibrio Roseibium. range strains, strains Roseibium Roseovarius, revealed genomic features colonisation association host, secretion systems eukaryote-like repeat proteins.Our work provides an in-depth analysis functional potential identifies combinations traits coral's ability withstand bleaching. Identifying characterising critical development effective probiotics boost climate Video Abstract.

Language: Английский

Citations

21
Localization and symbiotic status of probiotics in the coral holobiont DOI Creative Commons
Pedro Cardoso,

L. Hill,

Helena D. M. Villela

et al.

mSystems, Journal Year: 2024, Volume and Issue: 9(5)

Published: April 12, 2024

ABSTRACT Corals establish symbiotic relationships with microorganisms, especially endosymbiotic photosynthetic algae. Although other microbes have been commonly detected in coral tissues, their identity and beneficial functions for host are unclear. Here, we confirm the outcomes of inoculation bacteria selected as probiotics use fluorescence situ hybridization (FISH) to define localization Pocillopora damicornis . Our results show first evidence inherent presence Halomonas sp. Cobetia native even before inoculation. Furthermore, relative enrichment these tissue-associated through corals correlates health improvements, such increases potential, productivity. study suggests status by indicating within gastrodermis epidermis correlating increased abundance active holobiont. This knowledge is crucial facilitate screening application that may not be transient members microbiome. IMPORTANCE Despite promising associated some scarce regarding bacterial cells found tissue, correlation between two aspects still missing. gap limits our understanding actual diversity coral-associated whether symbionts beneficial. Some researchers, example, suggesting probiotic should only focus on very few known bacteria, Endozoicomonas sp., assuming currently tested tissue-associated. provide specific FISH probes expand probiotics. The microorganisms (BMCs) inside tissues gastric cavities also supports notion direct interactions underpin role. a new breakthrough; argue against possibility positive effects BMCs due factors related interaction, simply feeds inoculated or change water quality.

Language: Английский

Citations

5
Phototrophic bacteria as potential probiotics for corals DOI Creative Commons
Eslam O. Osman, Neus Garcías-Bonet, Pedro Cardoso

et al.

npj Biodiversity, Journal Year: 2025, Volume and Issue: 4(1)

Published: April 29, 2025

Coral-associated microorganisms provide crucial nutritional, protective, and developmental benefits, yet many functional traits remain unexplored. Phototrophic bacteria may enhance coral nutrition reduce oxidative stress during bleaching via photosynthesis antioxidant production. Despite this potential, their role in the holobiont's energy budget heat resilience is understudied. This review explores potential of phototrophic to health under environmental stress.

Language: Английский

Citations

0
Assessing the contribution of bacteria to the heat tolerance of experimentally evolved coral photosymbionts DOI Creative Commons
Justin Maire, Pranali Deore,

Vanta Jameson

et al.

Environmental Microbiology, Journal Year: 2023, Volume and Issue: 25(12), P. 3298 - 3318

Published: Oct. 17, 2023

Coral reefs are extremely vulnerable to ocean warming, which triggers coral bleaching-the loss of endosymbiotic microalgae (Symbiodiniaceae) from tissues, often leading death. To enhance climate resilience, the symbiont, Cladocopium proliferum was experimentally evolved for >10 years under elevated temperatures resulting in increased heat tolerance. Bacterial 16S rRNA gene metabarcoding showed composition intra- and extracellular bacterial communities heat-evolved strains significantly different that wild-type strains, suggesting bacteria responded temperatures, may even play a role C. thermal assess whether microbiome transplantation could tolerance sensitive proliferum, we transplanted strain subjected it acute stress. Microbiome resulted incorporation only 30 low-abundance into cultures, while relative abundance 14 pre-existing doubled inoculated versus uninoculated samples. Inoculation with either or boosted growth, although no difference observed between two inoculation treatments. This study provides evidence Symbiodiniaceae-associated respond selection contribute adaptation change.

Language: Английский

Citations

10
The Coral Holobiont DOI
Érika P. Santoro, Yusuf C. El‐Khaled,

Phillipe M. Rosado

et al.

Coral reefs of the world, Journal Year: 2025, Volume and Issue: unknown, P. 95 - 104

Published: Jan. 1, 2025

Language: Английский

Citations

0
Challenges for coral restoration in Southwestern Atlantic reefs: guidelines for ethical and sustainable practices DOI
Miguel Mies, Guilherme Ortigara Longo, Adalto Bianchini

et al.

Biodiversity and Conservation, Journal Year: 2025, Volume and Issue: unknown

Published: April 17, 2025

Language: Английский

Citations

0
Inoculation with Roseovarius increases thermal tolerance of the coral photosymbiont, Breviolum minutum DOI Creative Commons

Karla Heric,

Justin Maire, Pranali Deore

et al.

Frontiers in Ecology and Evolution, Journal Year: 2023, Volume and Issue: 11

Published: Aug. 10, 2023

Coral reefs are diverse marine ecosystems that have tremendous ecological and cultural value support more than 25% of eukaryote biodiversity. Increased ocean temperatures light intensity trigger coral bleaching, the breakdown relationship between corals their photosymbionts, dinoflagellates family Symbiodiniaceae. This leaves without primary energy source, thereby leading to starvation and, often, death. bleaching is hypothesized occur due an overproduction reactive oxygen species (ROS) by Symbiodiniaceae, which subsequently accumulate in tissues. Bacterial probiotics been proposed as approach mitigate reducing ROS levels holobiont through bacterial antioxidant production. Both Symbiodiniaceae known associate with bacteria. However, Symbiodiniaceae-bacteria relationship, its impact on thermal tolerance, remains a poorly studied area. In this study, cultured Breviolum minutum were treated antibiotics reduce load. The cultures inoculated isolates from genus Roseovarius isolated same B. culture showed either high or low ROS-scavenging abilities. then exposed experimental heat stress for 16 days, health was monitored measurements cell density photochemical efficiency photosystem II. It found higher abilities greater growth at elevated temperatures, compared strain lower suggests may play role fitness temperatures. Analysis Symbiodiniaceae-associated communities 16S rRNA gene metabarcoding revealed relative abundance increased following inoculation temperature exposure, highlighting contribution they shielding stress, although other community changes also contributed these observations. study begins unpick bacteria opens door use reef conservation approaches.

Language: Английский

Citations

8