ISME communicationsPub Date : 2025-01-25eCollection Date: 2025-01-01DOI: 10.1093/ismeco/ycaf010
Luis A Saona, Christian I Oporto, Pablo Villarreal, Kamila Urbina, Cristian Correa, Julian F Quintero-Galvis, Paulo Moreno-Meynard, Frida I Piper, Juliana A Vianna, Roberto F Nespolo, Francisco A Cubillos
{"title":"High ectomycorrhizal relative abundance during winter at the treeline.","authors":"Luis A Saona, Christian I Oporto, Pablo Villarreal, Kamila Urbina, Cristian Correa, Julian F Quintero-Galvis, Paulo Moreno-Meynard, Frida I Piper, Juliana A Vianna, Roberto F Nespolo, Francisco A Cubillos","doi":"10.1093/ismeco/ycaf010","DOIUrl":"10.1093/ismeco/ycaf010","url":null,"abstract":"<p><p>The rhizosphere is the soil region around plant roots hosting a diverse microbial community, influencing nutrient availability and how plants react to extreme conditions. However, our understanding of the fungi biodiversity and the impact of environmental variations on this biodiversity is still in its infancy. Our study investigates fungal communities' diversity and functional traits in the rhizosphere of <i>Nothofagus pumilio,</i> one of the few winters deciduous treeline species in the world, forming the treeline in southern South America. At four distinct locations covering 10° latitude, we collected soil samples at treeline and 200 m below over four seasons during a single year. We employed ITS metabarcoding to elucidate fungal community structures. Our results reveal that fungal diversity was mainly determined by latitudinal variation, with higher levels during warmer seasons and lower altitudes. Interestingly, we found a marked dominance of ectomycorrhizal fungi at the treeline, particularly during the winter. In contrast, saprotrophic fungi were more abundant at lower altitudes, particularly during the warmer spring and summer seasons. These findings highlight the temporal and spatial dynamics of rhizospheric fungal communities and their potential roles in ecological processes, emphasizing the value of these communities as indicators of environmental change in high-elevation forests.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf010"},"PeriodicalIF":5.1,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11815889/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143412023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ISME communicationsPub Date : 2025-01-23eCollection Date: 2025-01-01DOI: 10.1093/ismeco/ycaf008
Chuen Zhang Lee, Sarah F Worsley, Charli S Davies, Ece Silan, Terry Burke, Jan Komdeur, Falk Hildebrand, Hannah L Dugdale, David S Richardson
{"title":"Metagenomic analyses of gut microbiome composition and function with age in a wild bird; little change, except increased transposase gene abundance.","authors":"Chuen Zhang Lee, Sarah F Worsley, Charli S Davies, Ece Silan, Terry Burke, Jan Komdeur, Falk Hildebrand, Hannah L Dugdale, David S Richardson","doi":"10.1093/ismeco/ycaf008","DOIUrl":"10.1093/ismeco/ycaf008","url":null,"abstract":"<p><p>Studies on wild animals, mostly undertaken using 16S metabarcoding, have yielded ambiguous evidence regarding changes in the gut microbiome (GM) with age and senescence. Furthermore, variation in GM function has rarely been studied in such wild populations, despite GM metabolic characteristics potentially being associated with host senescent declines. Here, we used 7 years of repeated sampling of individuals and shotgun metagenomic sequencing to investigate taxonomic and functional changes in the GM of Seychelles warblers (<i>Acrocephalus sechellensis</i>) with age. Our results suggest that taxonomic GM species richness declines with age and in the terminal year, with this terminal decline occurring consistently across all ages. Taxonomic and functional GM composition also shifted with host age. However, the changes we identified occurred linearly with age (or even mainly during early years prior to the onset of senescence in this species) with little evidence of accelerated change in later life or during their terminal year. Therefore, the results suggest that changes in the GM with age are not linked to senescence. Interestingly, we found a significant increase in the abundance of a group of transposase genes with age, which may accumulate passively or due to increased transposition induced as a result of stressors that arise with age. These findings reveal taxonomic and functional GM changes with age, but not senescence, in a wild vertebrate and provide a blueprint for future wild functional GM studies linked to age and senescence.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf008"},"PeriodicalIF":5.1,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11833318/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143451167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ISME communicationsPub Date : 2025-01-21eCollection Date: 2025-01-01DOI: 10.1093/ismeco/ycaf007
Nastasia J Freyria, Thais C de Oliveira, Arnaud Meng, Eric Pelletier, Connie Lovejoy
{"title":"Shotgun metagenomics reveals the flexibility and diversity of Arctic marine microbiomes.","authors":"Nastasia J Freyria, Thais C de Oliveira, Arnaud Meng, Eric Pelletier, Connie Lovejoy","doi":"10.1093/ismeco/ycaf007","DOIUrl":"10.1093/ismeco/ycaf007","url":null,"abstract":"<p><p>Polar oceanographic regions are exposed to rapid changes in temperature, salinity, and light fields that determine microbial species distributions, but resilience to an increasingly unstable climate is unknown. To unravel microbial genomic potential of the Northern Baffin Bay's polynya, we constructed eight metagenomes from the same latitude but targeting two sides of <i>Pikialasorsuaq</i> (The North Water) that differ by current systems, stratification, and temperature regimes. Samples from the surface and subsurface chlorophyll maximum (SCM) of both sides were collected 13 months apart. Details of metabolic pathways were determined for 18 bacteria and 10 microbial eukaryote metagenome-assembled genomes (MAGs). The microbial eukaryotic MAGs were associated with the dominant green algae in the Mamiellales and diatoms in the Mediophyceae, which tended to respectively dominate the eastern and western sides of <i>Pikialasorsuaq</i>. We show that microbial community taxonomic and functional signatures were ca. 80% similar at the latitude sampled with only 20% of genes associated with local conditions. From the metagenomes we found genes involved in osmotic regulation, antifreeze proteins, and photosystem protection, with hydrocarbon biodegradation and methane oxidation potential detected. The shared genomic compliment was consistent with adaptation to the Arctic's extreme fluctuating conditions, with implications for their evolutionary history and the long-term survival of a pan-arctic microbiome. In particular, previously unrecognized genetic capabilities for methane bio-attenuation and hydrocarbon metabolism in eukaryotic phytoplankton suggest adaptation to dark conditions that will remain, despite climate warming, in the high latitude offshore waters of a future Arctic.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf007"},"PeriodicalIF":5.1,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11847657/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143494865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ISME communicationsPub Date : 2025-01-14eCollection Date: 2025-01-01DOI: 10.1093/ismeco/ycaf005
Anna Chen, Rachel M Covitz, Abigail A Folsom, Xiangxi Mu, Ronald F Peck, Suegene Noh
{"title":"Symbiotic T6SS affects horizontal transmission of <i>Paraburkholderia bonniea</i> among <i>Dictyostelium discoideum</i> amoeba hosts.","authors":"Anna Chen, Rachel M Covitz, Abigail A Folsom, Xiangxi Mu, Ronald F Peck, Suegene Noh","doi":"10.1093/ismeco/ycaf005","DOIUrl":"10.1093/ismeco/ycaf005","url":null,"abstract":"<p><p>Three species of <i>Paraburkholderia</i> are able to form facultative symbiotic relationships with the amoeba, <i>Dictyostelium discoideum</i>. These symbiotic <i>Paraburkholderia</i> share a type VI secretion system (T6SS) that is absent in other close relatives. We tested the phenotypic and transcriptional effect of <i>tssH</i> ATPase gene disruption in <i>P. bonniea</i> on its symbiosis with <i>D. discoideum</i>. We hypothesized that the ∆<i>tssH</i> mutant would have a significantly reduced ability to affect host fitness or transmit itself from host to host. We found that the T6SS does not directly affect host fitness. Instead, wildtype <i>P. bonniea</i> had significantly higher rates of horizontal transmission compared to ∆<i>tssH</i>. In addition, we observed significant differences in the range of infection prevalence achieved by wildtype vs. ∆<i>tssH</i> symbionts over multiple host social stages in the absence of opportunities for environmental symbiont acquisition. Successful symbiont transmission significantly contributes to sustained symbiotic association. Therefore, the shared T6SS appears necessary for a long-term evolutionary relationship between <i>D. discoideum</i> and its <i>Paraburkholderia</i> symbionts. The lack of difference in host fitness outcomes was confirmed by indistinguishable host gene expression patterns between hosts infected by wildtype or ∆<i>tssH P. bonniea</i> in an RNA-seq time series. These data also provided insight into how <i>Paraburkholderia</i> symbionts may evade phagocytosis by its amoeba host. Most significantly, cellular oxidant detoxification and lysosomal hydrolase delivery appear to be subject to the push and pull of host-symbiont crosstalk.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf005"},"PeriodicalIF":5.1,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11882306/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143569188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ISME communicationsPub Date : 2025-01-13eCollection Date: 2025-01-01DOI: 10.1093/ismeco/ycaf004
Rachel Los, Tobias Fecker, P A M van Touw, Rinke J van Tatenhove-Pel, Timon Idema
{"title":"Time of first contact determines cooperator success in a three-member microbial consortium.","authors":"Rachel Los, Tobias Fecker, P A M van Touw, Rinke J van Tatenhove-Pel, Timon Idema","doi":"10.1093/ismeco/ycaf004","DOIUrl":"10.1093/ismeco/ycaf004","url":null,"abstract":"<p><p>Microbial communities are characterized by complex interaction, including cooperation and cheating, which have significant ecological and applied implications. However, the factors determining the success of cooperators in the presence of cheaters remain poorly understood. Here, we investigate the dynamics of cooperative interactions in a consortium consisting of a cross-feeding pair and a cheater strain using individual-based simulations and an engineered <i>L. cremoris</i> toy consortium. Our simulations reveal first contact time between cooperators as a critical predictor for cooperator success. By manipulating the relative distances between cooperators and cheaters or the background growth rates, influenced by the cost of cooperation, we can modulate this first contact time and influence cooperator success. Our study underscores the importance of cooperators coming into contact with each other on time, which provides a simple and generalizable framework for understanding and designing cooperative interactions in microbial communities. These findings contribute to our understanding of cross-feeding dynamics and offer practical insights for synthetic and biotechnological applications.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf004"},"PeriodicalIF":5.1,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11879117/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143558435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ISME communicationsPub Date : 2025-01-10eCollection Date: 2025-01-01DOI: 10.1093/ismeco/ycaf003
Ze Ren, Wei Luo, Huirong Li, Haitao Ding, Yunlin Zhang
{"title":"Decrypting the phylogeny and metabolism of microbial dark matter in green and red Antarctic snow.","authors":"Ze Ren, Wei Luo, Huirong Li, Haitao Ding, Yunlin Zhang","doi":"10.1093/ismeco/ycaf003","DOIUrl":"10.1093/ismeco/ycaf003","url":null,"abstract":"<p><p>Antarctic snow harbors diverse microorganisms, including pigmented algae and bacteria, which create colored snow patches and influence global climate and biogeochemical cycles. However, the genomic diversity and metabolic potential of colored snow remain poorly understood. We conducted a genome-resolved study of microbiomes in colored snow from 13 patches (7 green and 6 red) on the Fildes Peninsula, Antarctica. Using metagenome assembly and binning, we reconstructed 223 metagenome-assembled genomes (MAGs), with 91% representing previously unexplored microbes. Green snow (GS) and red snow (RS) showed distinct MAGs profile, with <i>Polaromonas</i> and <i>Ferruginibacter</i> as the most abundant genera, respectively. GS exhibited higher alpha diversity with more unique and enriched MAGs, while RS showed greater variability with higher beta diversity. All MAGs contained genes encoding auxiliary activities (AAs), carbohydrate esterases (CEs), glycoside hydrolases (GHs), and glycosyl transferases (GTs), indicating microbial degradation of complex carbon substrates. The most abundant enzymes included GT2 (cellulose synthase), GT4 (sucrose synthase), CE1 (acetyl xylan esterase), GT41 (peptide beta-N-acetylglucosaminyltransferase), and CE10 (arylesterase). GS had a higher abundance of GTs, whereas RS was enriched in GHs. Furthermore, 56% of MAGs contained genes for inorganic nitrogen cycling, with 18 gene families involved in assimilatory nitrate reduction, dissimilatory nitrate reduction, and denitrification. Potential coupling of nitrogen cycling and carbohydrate metabolism was observed at both genome and community levels, suggesting close links between these pathways, particularly through nitrate reduction during carbohydrate degradation. This study enhances our understanding of microbial metabolic functions in polar ecosystems and highlights their roles in maintaining Antarctic ecological stability.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf003"},"PeriodicalIF":5.1,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11765414/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143049174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Contrasting diversity patterns between microeukaryotic and prokaryotic communities in cold-seep sediments.","authors":"Zhimeng Xu, Jiawei Chen, Wenzhao Liang, Zhao Liang Chen, Wenxue Wu, Xiaomin Xia, Bingzhang Chen, Ding He, Hongbin Liu","doi":"10.1093/ismeco/ycaf002","DOIUrl":"10.1093/ismeco/ycaf002","url":null,"abstract":"<p><p>Cold seeps are hotspots of biodiversity. However, the quantification of the microbial diversity, particularly that of microeukaryotes, remains scarce and little is known about the active groups. In this study we investigated the diversity and activity of prokaryotes and microeukaryotes in the Haima cold seep sediments in the northern South China Sea using both DNA (whole community) and RNA (active community) signatures. We found that, in general, prokaryotes had lower diversity in the seep sediment than in non-seep regions while microeukaryotes showed the opposite pattern. This finding could be explained by the dominance of homogeneous selection in the prokaryotic community while microeukaryotic communities were less affected by environmental selection, harboring high richness of abundant groups in the seep regions. The compositional difference between DNA and RNA communities was much larger in microeukaryotes than prokaryotes, which could be reflected by the large number of inactive microeukaryotic taxa. Compared to the whole community, the seep-active groups, e.g. among microeukaryotes, <i>Breviatea, Labyrinthulomycetes</i>, and <i>Apicomplexa</i> were more sensitive to and directly influenced by environmental factors, suggesting their pivotal roles in ecosystem biodiversity and functions. This study provides insight into the distinct diversity patterns and regulating mechanisms that occur between prokaryotic and microeukaryotic communities in cold-seep sediments, deepening our understanding of microbial ecology in deep-sea extreme habitats.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf002"},"PeriodicalIF":5.1,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11879339/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143560290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ISME communicationsPub Date : 2025-01-07eCollection Date: 2025-01-01DOI: 10.1093/ismeco/ycae169
Léa Prigent, Julien Quéré, Martin Plus, Mickael Le Gac
{"title":"Sexual reproduction during diatom bloom.","authors":"Léa Prigent, Julien Quéré, Martin Plus, Mickael Le Gac","doi":"10.1093/ismeco/ycae169","DOIUrl":"10.1093/ismeco/ycae169","url":null,"abstract":"<p><p>Phytoplankton supports food webs in all aquatic ecosystems. Ecological studies highlighted the links between environmental variables and species successions <i>in situ</i>. However, the role of life cycle characteristics on phytoplankton community dynamics remains poorly characterized. In diatoms, sexual reproduction creates new genetic combinations and prevents excessive cell size miniaturization. It has been extensively studied <i>in vitro</i> but seldom in the natural environment. Here, analyzing metatranscriptomic data in the light of the expression patterns previously characterized <i>in vitro</i>, we identified a synchronized and transient sexual reproduction event during a bloom of the toxic diatom species <i>Pseudo-nitzschia australis</i>. Despite the complexity of environmental conditions encountered <i>in situ,</i> sexual reproduction appeared to be the strongest differential gene expression signal that occurred during the bloom. The potential link between environmental conditions and the initiation of sexual reproduction remain to be determined, but sexual reproduction probably had a major impact on the bloom dynamic.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycae169"},"PeriodicalIF":5.1,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11749564/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143017585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ISME communicationsPub Date : 2025-01-06eCollection Date: 2025-01-01DOI: 10.1093/ismeco/ycaf001
Sergio E Morales, Sven P Tobias-Hünefeldt, Evelyn Armstrong, William S Pearman, Kirill Bogdanov
{"title":"Marine phytoplankton impose strong selective pressures on <i>in vitro</i> microbiome assembly, but drift is the dominant process.","authors":"Sergio E Morales, Sven P Tobias-Hünefeldt, Evelyn Armstrong, William S Pearman, Kirill Bogdanov","doi":"10.1093/ismeco/ycaf001","DOIUrl":"10.1093/ismeco/ycaf001","url":null,"abstract":"<p><p>Phytoplankton are known ecosystem engineers that modulate ocean community assembly processes, but the universality and extent of their microbiome control remains unclear. We used <i>in vitro</i> incubations and 16S ribosomal RNA gene amplicon sequencing to test the influence of Southern and South Pacific oceans dominant phytoplankton on assembly processes and community successions in response to phytoplankton blooms. Phytoplankton grown with reduced-diversity cultures or supplemented with exogenously added microbiomes showed reduced diversity, suggesting environmental filtering. Community profiles were distinct under all culture conditions, further confirming strong selection for specific microbiomes based on phytoplankton. Analysis of core, abundant, and rare organisms in each culture condition showed a conserved response in which core organisms were enriched under conditions of exogenously added phytoplankton. Progression through phytoplankton growth phases selected first for rare and abundant organisms, with increased selection for core members during the exponential phase and relaxing of selection during the death phase, as seen throughout incubations for microbiome-only controls. Surprisingly, selection process quantification identified drift as the dominant process across all conditions and growth phases, with homogenous selection and dispersal limitation accounting for the remainder. Altogether, using Southern Ocean-derived model organisms we confirmed the role phytoplankton play in community assembly but also demonstrated that stochastic processes still predominately drive community selection.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf001"},"PeriodicalIF":5.1,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11843096/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143484837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Soil microbial carbon use efficiency differs between mycorrhizal trees: insights from substrate stoichiometry and microbial networks.","authors":"Jing Yu, Jingyi Yang, Lingrui Qu, Xiaoyi Huang, Yue Liu, Ping Jiang, Chao Wang","doi":"10.1093/ismeco/ycae173","DOIUrl":"10.1093/ismeco/ycae173","url":null,"abstract":"<p><p>The role of mycorrhizal associations in controlling forest soil carbon storage remains under debate. This uncertainty is potentially due to an incomplete understanding of their influence on the free-living soil microbiome and its functions. In this study, rhizosphere and non-rhizosphere soils were collected from eight arbuscular mycorrhizal (AM) and seven ectomycorrhizal (ECM) tree species in a temperate forest. We employed high-throughput sequencing and <sup>18</sup>O-H<sub>2</sub>O labeling to analyze the soil microbial community and carbon use efficiency (CUE), respectively. We find microbial respiration rates are higher in rhizosphere than that in non-rhizosphere soils for ECM trees, whereas microbial growth rates show no significant differences. Consequently, microbial CUE is lower in rhizosphere compared to non-rhizosphere soils for ECM trees. In addition, we find that non-rhizosphere soils from ECM trees exhibited higher CUE compared to those from AM trees. Furthermore, we observe that bacterial-fungal co-occurrence networks in ECM soils exhibit greater complexity relative to AM ones. Using random forest and structural equation modeling analyses, we find that microbial stoichiometric carbon/nitrogen imbalance and network complexity are key predictors of soil microbial CUE for AM and ECM trees, respectively. Our findings shed new light on the pivotal role of mycorrhizal associations in shaping free-living microbial communities and their metabolic characteristics in the studied soils. These insights are critical for predicting soil carbon sequestration in response to shifts in ECM and AM species within temperate forest under climate change.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycae173"},"PeriodicalIF":5.1,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11742255/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143017587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}