Microbial Dynamics in Sponge Holobionts

Marine sponges harbour complex microbial assemblages that function as an integrated holobiont, underpinning host physiology, ecology and evolution. These symbiont communities are often highly specific to their sponge host, forming stable core microbiomes alongside variable peripheral taxa. Two broad categories of sponge–microbe associations have been recognised: high microbial abundance (HMA) sponges, which host diverse and dense consortia, and low microbial abundance (LMA) sponges, characterised by simpler communities. Symbionts perform a range of metabolic functions, from autotrophic processes such as ammonia oxidation and carbon fixation to heterotrophic pathways including methanotrophy and degradation of organic compounds. Metabolomic profiling has revealed that microbial metabolites shape host development, immunity and chemical defence, while multi-omics studies demonstrate that vertical transmission and selective horizontal acquisition together drive community assembly. These microbial processes, fuelled by the sponge’s prolific water filtration, contribute substantially to marine nutrient cycling and have global implications for carbon, nitrogen and phosphorus biogeochemistry. Understanding microbial dynamics in sponge holobionts is therefore essential both for fundamental marine biology and for predicting ecosystem responses to environmental change.

Research from Nature Portfolio

Recent studies integrating microbiome characterisation with metabolomics have compared coexisting Mediterranean sponges to reveal species-specific microbial and metabolic signatures. These analyses showed that some hosts rely on heterotrophic symbionts, while others support autotrophic communities, and yet all share a core suite of metabolites despite differences at the single-compound level. Such findings suggest that niche diversification among holobionts can arise through convergent evolution of microbial functions. A global survey of sponge microbiomes has further demonstrated that sponge hosts act as reservoirs of exceptional microbial diversity, with community structure shaped more by host identity and phylogenetic complexity than by environmental opportunism. Specialists and generalists coexist across sponge lineages, and convergent community organisation emerges despite independent assembly histories, emphasising the evolutionary resilience and ecological significance of sponge–microbe partnerships.

Microbial Dynamics in Sponge Holobionts publication trend

The graph below shows the total number of articles in microbial dynamics in sponge holobionts across all publications each year (not limited to Nature Index journals).

Technical terms

Holobiont: The assemblage of a host organism and its associated microbial communities operating as a single ecological unit.

Microbiome: The collective genomes and metabolic activities of microorganisms living in association with a host or habitat.

Metabolomics: The comprehensive study of small molecules and metabolic pathways within a biological system.

Autotrophy: A metabolic process by which organisms fix inorganic carbon to synthesise organic compounds.

Heterotrophy: A metabolic process by which organisms consume and derive energy from organic compounds produced by others.

Methanotrophy: The biological oxidation of methane by specialised bacteria.

References

1. The sponge holobiont in a changing ocean: from microbes to ecosystems. Microbiome (2018).
2. Predicting the HMA-LMA Status in Marine Sponges by Machine Learning. Frontiers in Microbiology (2017).
3. Phylogenetic signal in the community structure of host-specific microbiomes of tropical marine sponges. Frontiers in Microbiology (2014).
4. Deep sequencing reveals exceptional diversity and modes of transmission for bacterial sponge symbionts. Environmental Microbiology (2010).
5. Bacterial aerobic methane cycling by the marine sponge-associated microbiome. Microbiome (2023).
6. Species-specific relationships between deep sea sponges and their symbiotic Nitrosopumilaceae. The ISME Journal: Multidisciplinary Journal of Microbial Ecology (2023).
7. Body-Plan Reorganization in a Sponge Correlates with Microbiome Change. Molecular Biology and Evolution (2023).
8. High microbiome and metabolome diversification in coexisting sponges with different bio-ecological traits. Communications Biology (2024).
9. Diversity, structure and convergent evolution of the global sponge microbiome. Nature Communications (2016).