ISME communications最新文献

{"title":"Daily microbial rhythms of the surface ocean interrupted by the new moon-a lipidomic study.","authors":"Jiwoon Hwang, Alexander Hayward, Laura E Sofen, Kathleen J Pitz, Francisco P Chavez, Bethanie R Edwards","doi":"10.1093/ismeco/ycaf044","DOIUrl":"10.1093/ismeco/ycaf044","url":null,"abstract":"<p><p>Lipids are essential biomolecules for cell physiology and are commonly used as biomarkers to elucidate biogeochemical processes over a large range of environments and timescales. Here, we use high-temporal-resolution lipidomic analysis to characterize the surface ocean community in the productive upwelling region overlying the Monterey Bay Canyon. We observed a strong diel signal with a drawdown of lipids at night and an increase during the day that seemed to correspond to wholesale removal of lipids from the surface ocean as opposed to internal metabolism. Individual lipid species were organized into coregulated groups that were interpreted as representing different phytoplankton guilds. Concentrations of long-chained triacylglycerols (TAGs) showed unique patterns over the course of five days. TAGs were used to estimate the amount of energy cycled through the surface ocean. These calculations revealed diurnal carbon cycling that was on scales comparable to net primary production. The diel pattern dissipated from most lipid modules on Day 3 as tidal forcing increased at our site with the advent of the new moon. Pigment analysis indicated that the community shifted from a diatom-dominated community to a more diverse assemblage, including more haptophytes, chlorophytes, and <i>Synechococcus</i> during the new moon. The shift in community appears to promote higher nutritional quality of biomass, with more essential fatty acids in the surface ocean during the spring tide. This analysis showcases the utility of lipidomics in characterizing community dynamics and underscores the importance of considering both diel and tidal timescales when sampling in productive coastal regions.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf044"},"PeriodicalIF":5.1,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11962720/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143775221","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":"Towards high-accuracy bacterial taxonomy identification using phenotypic single-cell Raman spectroscopy data.","authors":"Guangyu Li, Zijian Wang, Chieh Wu, Dongqi Wang, Il Han, Jangho Lee, David R Kaeli, Jennifer G Dy, Kilian Q Weinberger, April Z Gu","doi":"10.1093/ismeco/ycaf015","DOIUrl":"https://doi.org/10.1093/ismeco/ycaf015","url":null,"abstract":"<p><p>Single-cell Raman Spectroscopy (SCRS) emerges as a promising tool for single-cell phenotyping in environmental ecological studies, offering non-intrusive, high-resolution, and high-throughput capabilities. In this study, we obtained a large and the first comprehensive SCRS dataset that captured phenotypic variations with cell growth status for 36 microbial strains, and we compared and optimized analysis techniques and classifiers for SCRS-based taxonomy identification. First, we benchmarked five dimensionality reduction (DR) methods, 10 classifiers, and the impact of cell growth variances using a SCRS dataset with both taxonomy and cellular growth stage labels. Unsupervised DR methods and non-neural network classifiers are recommended for at a balance between accuracy and time efficiency, achieved up to 96.1% taxonomy classification accuracy. Second, accuracy variances caused by cellular growth variance (<2.9% difference) was found less than the influence from model selection (up to 41.4% difference). Remarkably, simultaneous high accuracy in growth stage classification (93.3%) and taxonomy classification (94%) were achievable using an innovative two-step classifier model. Third, this study is the first to successfully apply models trained on pure culture SCRS data to achieve taxonomic identification of microbes in environmental samples at an accuracy of 79%, and with validation via Raman-FISH (fluorescence <i>in situ</i> hybridization). This study paves the groundwork for standardizing SCRS-based biotechnologies in single-cell phenotyping and taxonomic classification beyond laboratory pure culture to real environmental microorganisms and promises advances in SCRS applications for elucidating organismal functions, ecological adaptability, and environmental interactions.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf015"},"PeriodicalIF":5.1,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11910137/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143652472","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":"Superior ability of dietary fiber utilization in obese breed pigs linked to gut microbial hydrogenotrophy.","authors":"Xuan Li, Chunlong Mu, Haiqin Wu, Erwin G Zoetendal, Ruihua Huang, Kaifan Yu, Weiyun Zhu","doi":"10.1093/ismeco/ycaf043","DOIUrl":"10.1093/ismeco/ycaf043","url":null,"abstract":"<p><p>Dietary fiber is widely recognized for its benefits to human health. Individual variations in the ability to degrade dietary fiber are influenced by the gut microbiome that may be associated with the host's metabolic phenotype and genetic diversity. This is exemplified by the distinct fiber digestibility observed in obese (e.g. Meishan) and lean-breed (e.g. Yorkshire) pigs. However, the underlying mechanisms remain unclear. The present study found that with the same diet under the same environment, the obese-type Meishan pigs showed greater dietary fiber digestibility and harbored higher abundances of polysaccharide-degrading bacteria (<i>Bacteroides</i>, <i>Treponema</i>, and <i>Paraprevotella</i>) compared to lean-type Yorkshire pigs. Metatranscriptomic profiling revealed that the elevated presence of <i>Bacteroides</i> contributed to the enrichment of carbohydrate-active enzymes, particularly those degrading arabinoxylan, indicating a preference for arabinoxylan as a substrate in Meishan pigs. Further enzymatic-product measurements, combined with microbial enzyme profiles, validated greater microbial conversion of xylose into short-chain fatty acids (SCFAs) in Meishan pigs. Additionally, higher abundances of hydrogenotrophic microbes (<i>Methanobrevibacter</i> and <i>Blautia</i>) were detected in the Meishan gut, along with the enrichment of methanogenesis and acetogenesis pathways. To determine whether methanogenesis drives inter-breed variation in arabinoxylan degradation, an <i>in vitro</i> experiment using the methanogen inhibitor, 2-bromoethanesulfonate (BES) was performed. The results confirmed that Meishan gut microbiome effectively reduced hydrogen accumulation through methanogenesis, promoting arabinoxylan degradation. Conversely, inhibiting methanogenesis by BES led to hydrogen accumulation, reduced SCFAs, β-xylosidase activity, and <i>Bacteroides</i> abundances. These findings demonstrate that the Meishan pigs have a superior ability of dietary fiber utilization with greater microbial conversion to more SCFAs, which is linked to stronger hydrogenotrophic methanogenesis. This study reinforces the role of gut microbial hydrogenotrophy in dietary fiber utilization in pigs.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf043"},"PeriodicalIF":5.1,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11937827/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143722538","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":"Inferring replication states of bacteria and viruses in enrichment cultures via long-read sequencing.","authors":"Sophie A Simon, André R Soares, Till L V Bornemann, Adrian Lange, Lea Griesdorn, Adrián Fuentes, Marie Dieckmann, Beate A Krok, S Emil Ruff, Michael Hügler, Cristina Moraru, Alexander J Probst","doi":"10.1093/ismeco/ycaf041","DOIUrl":"10.1093/ismeco/ycaf041","url":null,"abstract":"<p><p>Most microorganisms cannot be cultured in isolation, necessitating sophisticated methods for studying their (eco)physiology. While numerous approaches can probe the activity of given microbes in enrichment cultures, no single technique can render simultaneous data on both metabolic capacities and mobile genetic elements. Here, we apply long-read sequencing to monitor the incorporation of non-canonical bases in genome-resolved metagenomic datasets and elucidate the replication patterns of both bacteria and phages. This technology enables the simultaneous reconstruction of both prokaryotic and viral genomes (alongside genomics downstream analyses like metabolic predictions), in addition to providing information regarding their replication in enrichment cultures. By spiking the base analog 5-bromo-2'-deoxyuridine (BrdU) into activated sludge microcosms, we determined that 114 of the 118 high-quality genomes recovered were actively replicating in enrichment cultures from activated sludge and identified both slow (low BrdU incorporation and change in abundance) and rapidly replicating organisms (high BrdU incorporation and change in abundance). Some of the genomes detected exhibited regions rich in BrdU that were predicted to represent prophages in their lytic cycle. Ultimately, this novel means of monitoring the replication responses of microbes, and deciphering their genomes and active mobile genetic elements will advance and empower strategies aimed at isolating previously uncultivated microbes in pure culture.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf041"},"PeriodicalIF":5.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11964896/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143782235","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":"A hunting ground for predatory bacteria at the Zhenbei seamount in the South China Sea.","authors":"Zhimeng Li, Dayu Zou, Rulong Liu, Juntong Pan, Junkai Huang, Jun Ma, Liting Huang, Jiani He, Lulu Fu, Xiaowei Zheng, Minxiao Wang, Jiasong Fang, Hailiang Dong, Meng Li, Li Huang, Xin Dai","doi":"10.1093/ismeco/ycaf042","DOIUrl":"10.1093/ismeco/ycaf042","url":null,"abstract":"<p><p>Seamounts are critical marine biodiversity hot spots, while the metabolic activity of their microbial community remains largely unknown. In this study, we investigated the diversity and activity of free-living and particle-attached microorganisms in the surface, middle, and bottom layers of seawater at the Zhenbei seamount in the South China Sea using omics approaches, including 16S ribosomal RNA (rRNA)/16S rDNA ratio analysis. Over 20 phyla were detected, with <i>Proteobacteria</i>, <i>Actinobacteriota</i>, <i>Cyanobacteria</i>, <i>Bacteroidota</i>, <i>Thaumarchaeota</i>, and <i>Planctomycetota</i> being predominant. Surprisingly, <i>Bdellovibrionota</i> and <i>Myxococcota</i>, the two well-known predatory bacteria, exhibited exceptionally higher rRNA/rDNA ratios than the other phyla, with rRNA abundances being 10- or even 200-fold higher than their rDNA abundances. These metabolically active predatory bacteria are mainly uncultured species. A total of 23 <i>Myxococcota</i> metagenome-assembled genomes (MAGs) and 12 <i>Bdellovibrionota</i> MAGs were assembled. The most highly overexpressed genes frequently detected in these MAGs were those that encode flagellum and pilus proteins as well as T4-like virus tail tube protein, indicating that these predator bacteria were likely active in hunting. Our results suggest that seamounts may serve as hunting grounds for predatory bacteria, which may be involved in controlling the flows of elements and energy in the seamount microbial communities and, thus, in shaping the seamount ecosystems.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf042"},"PeriodicalIF":5.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11937823/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143722932","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":"Warming stimulates cellulose decomposition by recruiting phylogenetically diverse but functionally similar microorganisms.","authors":"Yifan Su, Xue Guo, Yamei Gao, Jiajie Feng, Linwei Wu, Jiesi Lei, Suo Liu, Qun Gao, Yufei Zeng, Wei Qin, Zheng Shi, Zhengxiong Liang, Zhencheng Ye, Mengting Yuan, Daliang Ning, Liyou Wu, Jizhong Zhou, Yunfeng Yang","doi":"10.1093/ismeco/ycae152","DOIUrl":"10.1093/ismeco/ycae152","url":null,"abstract":"<p><p>Cellulose is the most abundant component of plant litter, which is critical for terrestrial carbon cycling. Nonetheless, it remains unknown how global warming affects cellulose-decomposing microorganisms. Here, we carried out a 3-year litterbag experiment to examine cellulose decomposition undergoing +3°C warming in a tallgrass prairie. Most cellulose-associated bacteria and fungi in litterbags were also detected in bulk soil, and bacteria in litterbags had higher community-level <i>rrn</i> copy numbers, larger genome sizes, and higher genome guanine-cytosine (GC) contents than those in bulk soil, implying higher growth rates. Warming stimulated soil respiration by 32.3% and accelerated mass loss of cellulose, concurring with the increase in relative abundances of most functional genes associated with carbon decomposition in litterbags. Incorporating cellulose-decomposing genes into an ecosystem model reduced model parameter uncertainty and showed that warming stimulated microbial biomass, activity, and soil carbon decomposition. Collectively, our study supports a trait-centric view since cellulose-decomposing genes or genomic traits are amenable for ecosystem modeling. By characterizing the phylogenetically diverse yet functionally similar cellulose-associated microorganisms and their responses to warming, we take a step toward more precise predictions of soil carbon dynamics under future climate scenarios.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycae152"},"PeriodicalIF":5.1,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11892950/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143598421","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":"Redox determines greenhouse gas production kinetics and metabolic traits in water-saturated thawing permafrost peat.","authors":"Eira Catharine Lødrup Carlsen, Jing Wei, Franck Lejzerowicz, Sigrid Trier Kjær, Sebastian Westermann, Dag O Hessen, Peter Dörsch, Alexander Eiler","doi":"10.1093/ismeco/ycaf009","DOIUrl":"10.1093/ismeco/ycaf009","url":null,"abstract":"<p><p>Redox conditions, influenced by the availability of oxygen, are expected to dictate the rate of CO₂ and CH₄ production and to shape the composition and metabolism of microbial communities. Here, we use thawing permafrost peat in thermokarst water under a gradient of initial O₂ concentrations to experimentally cover the variability in redox conditions potentially found across thawing landscapes. The three main greenhouse gases, CO₂, CH₄ and N₂O, responded differently to O₂ absence. CO₂ production along the O₂ gradient could be modeled by the Michaelis Menten equation revealing a sharp decrease when oxygen dropped under 100 μM. Under anoxic conditions CO₂ yield decreased by 98% and maximum net production rate by 85% when compared to oxic conditions during the 11 days after thaw. N₂O production was observed under anoxic conditions, while CH₄ yield and CH₄ accumulation rates did not differ across the redox gradient. The latter is due to the release of stored CH₄ due to thawing. Differences between oxic and anoxic conditions were reflected in the microbial genomic composition, with changes in taxonomic and functional groups, such as N₂O reducers, fermenters, denitrifiers and sulfur reducers increasing under anoxic conditions. Genomic changes towards less efficient central metabolism further explained the CO₂ production yields and rates limited by O₂ availability as predicted by thermodynamics. Together with the Michaelis Menten models the metabolic reconstruction pinpoint to critical thresholds of CO₂ release at suboxic conditions and thus need to be considered when explaining and modeling highly variable CO₂ emissions across thawing landscapes.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf009"},"PeriodicalIF":5.1,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11922181/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143665532","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":"Estimates of microbial community stability using relative invader growth rates are robust across levels of invader species richness.","authors":"Meaghan Castledine, Daniel Padfield, Angus Buckling","doi":"10.1093/ismeco/ycaf040","DOIUrl":"https://doi.org/10.1093/ismeco/ycaf040","url":null,"abstract":"<p><p>A key feature of natural communities is that the species within them stably coexist. A common metric used to test community stability is the ability of each species to invade from rare. A potential issue with this measurement is that single species are invaded from rare, while in natural communities, multiple species would likely decline simultaneously following perturbations. This is especially common in microbes which can be rapidly disturbed by environmental stressors. If species coexistence is dependent on indirect interactions among community members, multiple species declining may result in community instability. As such, invading a single species into a community may overestimate the stability of a community when multiple species decline. Here, we compare estimates of community stability in a five species microbial community to experimental results in which multiple species are simultaneously invaded. Our results showed that single species invasions were qualitatively predictive of whole community stability when multiple species are invaded simultaneously. However, quantitative values of relative invader growth rate were less comparable, being non-significantly different in most comparisons in three out of five species. This was emphasized by the lack of correlation between exact values of growth rates under single or multi-species invasion. This work provides experimental support for the robustness of using invasion growth rate of single species to infer qualitative estimates of community stability.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf040"},"PeriodicalIF":5.1,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11994029/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143993397","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":"Horizontal transmission of symbiotic bacteria and host selective sweep in the giant clam <i>Tridacna crocea</i>.","authors":"Cong Liu, Jian Zhang, Qiqi Li, Yuehuan Zhang, Si Zhang, Ziniu Yu, Jun Li, Jie Li","doi":"10.1093/ismeco/ycaf037","DOIUrl":"10.1093/ismeco/ycaf037","url":null,"abstract":"<p><p>Giant clams, with their significant ecological importance, depend on associated bacteria for their health and development, yet the transmission modes and succession of community dynamics of these bacteria remain poorly understood. This study employed 16S rRNA gene sequencing and microscopy to investigate the transmission and community dynamics of symbiotic bacteria in the giant clam <i>Tridacna crocea</i> during early developmental stages (fertilized eggs, blastocyst, D-larvae, and pediveliger larvae). Fluorescence in situ hybridization and transmission electron microscopy did not detect internal symbiotic bacteria in fertilized eggs and adult gonad gametes, but scanning electron microscopy revealed microbial structures on egg surface microvilli, suggesting their role as microbial carriers. 16S rRNA sequencing confirmed microbial presence in fertilized eggs, indicating bacterial acquisition via external vertical transmission (adherence to microvilli) or horizontal transmission. Given the lack of internalized bacteria in reproductive organs, we prefer to classify the symbiotic bacteria acquisition as horizontal transmission. Microbial community analysis showed that <i>T. crocea</i> acquired a significant portion of its microbiome from seawater throughout its development. Before reaching the pediveliger stage, the bacterial community composition closely resembled that of the surrounding seawater, primarily featuring the family <i>Rhodobacteraceae</i>. As <i>T. crocea</i> matured, the host's selective pressure increased (e.g. deterministic assembly), which simplified the microbial community and reduced diversity. During the pediveliger stage, the genus <i>Endozoicomonas</i> became dominant, forming a large proportion of the bacterial community within the gonads. This highlights the ecological significance of host-microbe interactions in maintaining biodiversity and driving ecosystem stability through dynamic community assembly processes.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf037"},"PeriodicalIF":5.1,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11919647/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143665530","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":"Probiotics prevent mortality of thermal-sensitive corals exposed to short-term heat stress.","authors":"Mareike de Breuyn, Malte Ostendarp, Yusuf C El-Khaled, Neus Garcias-Bonet, Susana Carvalho, Christian Wild, Raquel S Peixoto","doi":"10.1093/ismeco/ycaf039","DOIUrl":"10.1093/ismeco/ycaf039","url":null,"abstract":"<p><p>The use of coral probiotics, i.e. beneficial microorganisms for corals (BMCs), is a novel approach to enhancing coral health under heat stress. While BMCs mitigate coral bleaching and mortality during prolonged heat stress conditions, their effectiveness in mitigating short-term acute heat stress remains understudied. This study investigates the effects of BMCs on two Red Sea hard coral species, <i>Acropora</i> cf. <i>hemprichii</i> and <i>Pocillopora verrucosa</i>, during short-term heat stress. Twelve coral fragments per species were allocated to each treatment across two temperature regimes (26°C and 32°C) for 48 hours, with half receiving BMC inoculation and half serving as controls. Results show BMC supplementation significantly prevented mortality in <i>Acropora</i> cf. <i>hemprichii</i> at 32°C, contrasting with a 100% mortality observed in the control group. Specifically, probiotic-inoculated <i>Acropora</i> cf. <i>hemprichii</i> at 32°C exhibited preserved primary production, a 12-13 fold increase in algal cell densities, 4-5 times higher <i>F_V/F_m</i> ratios, and 4-5 and 2-3 times higher chlorophyll <i>a</i> and <i>c₂</i> concentrations, respectively, compared to their untreated conspecifics. All <i>P. verrucosa</i> colonies survived the 32°C exposure without tissue loss or reduced holobiont function in both control and BMC treatments. These findings underscore the rapid effects of BMC inoculation, initiated just 2 hours prior to acute heat stress, in protecting heat-sensitive <i>Acropora</i> cf. <i>hemprichii</i> against mortality and adverse photo-physiological changes, with beneficial effects visible within 2 days. Recognizing the critical timeframe for beneficial effects is paramount for management strategies to address heat-sensitive corals on natural reefs, such as implementing probiotic interventions before anticipated marine heatwaves.</p>","PeriodicalId":73516,"journal":{"name":"ISME communications","volume":"5 1","pages":"ycaf039"},"PeriodicalIF":5.1,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11948994/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143733504","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}