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Nakano A. Effect of sand minerals on microbially induced carbonate precipitation by denitrification. CHEMOSPHERE 2024; 363:142890. [PMID: 39025311 DOI: 10.1016/j.chemosphere.2024.142890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 07/15/2024] [Accepted: 07/16/2024] [Indexed: 07/20/2024]
Abstract
Soil improvement techniques utilizing the metabolic functions of microorganisms, including microbially induced carbonate precipitation (MICP), have been extensively researched over the past few decades as part of bio-inspired geotechnical engineering research. Given that metabolic reactions in microorganisms produce carbonate minerals, an enhanced understanding of microbial interaction with soils could improve the effectiveness of MICP as a soil improvement technique. Therefore, this study investigated the effects of sands on MICP by denitrification to employ MICP for geotechnical soil improvement. Under the coexistence of natural sand and artificial silica sand, nitrate-reducing bacteria were cultured in a mixed liquid medium with nitrate, acetate, and calcium ions at 37 °C. Nitrate reduction occurred only in the presence of natural sand. However, the lack of chemical weathering of the composed minerals likely prevented the progress of bacterial growth and nitrate reduction in artificial silica sands. For natural sand, artificial chemical weathering by acid wash and ferrihydrite coating of the sand improved bacterial growth and accelerated nitrate reduction. The calcium carbonate formation induced by denitrification was also influenced by the state of the minerals in the soil and the nitrate reduction rate. The observed MICP enhancement is due to the involvement of coexisting secondary minerals like ferrihydrite with large specific surface areas and surface charges, which may improve the reaction efficiency by serving as adsorbents for bacteria and electron donors and acceptors in the solid phases, thereby promoting the precipitation and crystallization of calcium carbonate on the surfaces. This crystal formation in the minerals provides valuable insights for improving sand solidification via MICP. Considering the interactions between the target soil and microorganisms is essential to improving MICP processes for ground improvement.
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Affiliation(s)
- Akiko Nakano
- Faculty of Agriculture, Kyushu University, 819-0395, 744 Motooka, Nishi-ku, Fukuoka, Japan.
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Ishaq SE, Ahmad T, Liang L, Xie R, Yu T, Wang Y, Wang F. Cultivation of Diverse Novel Marine Bacteria from Deep Ocean Sediment Using Spent Culture Supernatant of Ca. Bathyarchaeia Enrichment. J Microbiol 2024; 62:611-625. [PMID: 38985432 DOI: 10.1007/s12275-024-00145-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 04/23/2024] [Accepted: 04/28/2024] [Indexed: 07/11/2024]
Abstract
Most microorganisms resist pure cultivation under conventional laboratory conditions. One of the primary issues for this un-culturability is the absence of biologically produced growth-promoting factors in traditionally defined growth media. However, whether cultivating microbes by providing spent culture supernatant of pivotal microbes in the growth medium can be an effective approach to overcome this limitation is still an under-explored area of research. Here, we used the spent culture medium (SCM) method to isolate previously uncultivated marine bacteria and compared the efficiency of this method with the traditional cultivation (TC) method. In the SCM method, Ca. Bathyarchaeia-enriched supernatant (10%) was used along with recalcitrant organic substrates such as lignin, humic acid, and organic carbon mixture. Ca. Bathyarchaeia, a ubiquitous class of archaea, have the capacity to produce metabolites, making their spent culture supernatant a key source to recover new bacterial stains. Both cultivation methods resulted in the recovery of bacterial species from the phyla Pseudomonadota, Bacteroidota, Actinomycetota, and Bacillota. However, our SCM approach also led to the recovery of species from rarely cultivated groups, such as Planctomycetota, Deinococcota, and Balneolota. In terms of the isolation of new taxa, the SCM method resulted in the cultivation of 80 potential new strains, including one at the family, 16 at the genus, and 63 at the species level, with a novelty ratio of ~ 35% (80/219). In contrast, the TC method allowed the isolation of ~ 10% (19/171) novel strains at species level only. These findings suggest that the SCM approach improved the cultivation of novel and diverse bacteria.
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Affiliation(s)
- Sidra Erum Ishaq
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Tariq Ahmad
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Lewen Liang
- Key Laboratory of Polar Ecosystem and Climate Change, Ministry of Education, School of Oceanography, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Ruize Xie
- Key Laboratory of Polar Ecosystem and Climate Change, Ministry of Education, School of Oceanography, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Tiantian Yu
- Key Laboratory of Polar Ecosystem and Climate Change, Ministry of Education, School of Oceanography, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Yinzhao Wang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Fengping Wang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China.
- Key Laboratory of Polar Ecosystem and Climate Change, Ministry of Education, School of Oceanography, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China.
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Li M, Raza M, Song S, Hou L, Zhang ZF, Gao M, Huang JE, Liu F, Cai L. Application of culturomics in fungal isolation from mangrove sediments. MICROBIOME 2023; 11:272. [PMID: 38082427 PMCID: PMC10712113 DOI: 10.1186/s40168-023-01708-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 10/19/2023] [Indexed: 12/18/2023]
Abstract
BACKGROUND Fungi play a crucial role in ecosystems, and they have been widely considered a promising source for natural compounds that are crucial for drug discovery. Fungi have a high diversity, but about 95% of them remain unknown to science. The description rate of fungi is very low, mainly due to the inability of most fungi to grow in artificial media, which could not provide a sufficiently similar environment to their natural habitats. Moreover, many species in nature are in a state of low metabolic activity which cannot readily proliferate without proper resuscitation. Previously developed culturomics techniques are mostly designed and applicable for bacteria, with few attempts for fungal isolation because of their significantly larger cell size and hyphal growth properties. RESULTS This study attempted to isolate previously uncultured and rare fungi from mangrove sediments using newly developed fungal enrichment culture method (FECM) and fungal isolation chips (FiChips). Comparison of fungal community composition at different enrichment stages showed that FECM had great influence on fungal community composition, with rare taxa increased significantly, thus improving the isolation efficiency of previously uncultured fungi. Similarly, in situ cultivation using FiChips has a significant advantage in detecting and culturing rare fungi, as compared to the conventional dilution plate method (DPM). In addition, based on morphological comparisons and phylogenetic analyses, we described and proposed 38 new ascomycetous taxa, including three new families, eight new genera, 25 new species, and two new combinations (presented in additional file 1). CONCLUSIONS Our study demonstrated that mangrove sediments harbor a high diversity of fungi, and our new isolation approaches (FECM and FiChips) presented a high efficiency in isolating hitherto uncultured fungi, which is potentially usable for fungal isolation in other similar environments. Video Abstract.
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Affiliation(s)
- Meng Li
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Mubashar Raza
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- Key Laboratory of Integrated Pest Management On Crops in Northwestern Oasis, Ministry of Agriculture and Rural Affairs, Institute of Plant Protection, Xinjiang Academy of Agricultural Sciences, Urumqi, 830091, China
| | - Shuang Song
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lingwei Hou
- Key Lab of Space Nutrition and Food Engineering, China Astronaut Research and Training Center, Beijing, 100094, China
| | - Zhi-Feng Zhang
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China
| | - Min Gao
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jun-En Huang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Fang Liu
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Lei Cai
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
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Yan C, Owen JS, Seo EY, Jung D, He S. Microbial Interaction is Among the Key Factors for Isolation of Previous Uncultured Microbes. J Microbiol 2023; 61:655-662. [PMID: 37589838 PMCID: PMC10477116 DOI: 10.1007/s12275-023-00063-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 06/13/2023] [Accepted: 06/18/2023] [Indexed: 08/18/2023]
Abstract
Pure cultivation of microbes is still limited by the challenges of microbial uncultivability, with most microbial strains unable to be cultivated under standard laboratory conditions. The experience accumulated from advanced techniques such as in situ cultivation has identified that microbial interactions exist in natural habitats but are absent in laboratory cultures. These microbial interactions are likely one of the key factors in isolating previously uncultured microbes. The need for better knowledge of the mechanisms operating in microbial interactions has led to various experiments that have utilized microbial interactions in different approaches to microbial cultivation. These new attempts to understand microbial interactions not only present a new perspective on microbial uncultivability but also provide an opportunity to access uncultured phylogenetically novel microbes with their potential biotechnology applications. In this review, we focus on studies of the mechanisms of microbial interaction where the growth of other microbes is affected. Additionally, we review some successful applications of microbial interactions in cultivation methods, an approach that can play an important role in the bioprospecting of untapped microbial resources.
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Affiliation(s)
- Chang Yan
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, 315832, People's Republic of China
- Ningbo Institute of Marine Medicine, Peking University, Ningbo, 315832, People's Republic of China
| | - Jeffrey S Owen
- Department of Environmental Science, Hankuk University of Foreign Studies, Yongin, 17035, Republic of Korea
| | - Eun-Young Seo
- Ningbo Institute of Marine Medicine, Peking University, Ningbo, 315832, People's Republic of China
| | - Dawoon Jung
- Ningbo Institute of Marine Medicine, Peking University, Ningbo, 315832, People's Republic of China.
| | - Shan He
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, 315832, People's Republic of China.
- Ningbo Institute of Marine Medicine, Peking University, Ningbo, 315832, People's Republic of China.
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Seo EY, Jung D, Epstein SS, Zhang W, Owen JS, Baba H, Yamamoto A, Harada M, Nakashimada Y, Kato S, Aoi Y, He S. A targeted liquid cultivation method for previously uncultured non-colony forming microbes. Front Microbiol 2023; 14:1194466. [PMID: 37362942 PMCID: PMC10288195 DOI: 10.3389/fmicb.2023.1194466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/10/2023] [Indexed: 06/28/2023] Open
Abstract
A large number of microbes are not able to form colonies using agar-plating methods, which is one of the reasons that cultivation based on solid media leaves the majority of microbial diversity in the environment inaccessible. We developed a new Non-Colony-Forming Liquid Cultivation method (NCFLC) that can selectively isolate non-colony-forming microbes that exclusively grow in liquid culture. The NCFLC method involves physically separating cells using dilution-to-extinction (DTE) cultivation and then selecting those that could not grow on a solid medium. The NCFLC was applied to marine samples from a coastal intertidal zone and soil samples from a forest area, and the results were compared with those from the standard direct plating method (SDP). The NCFLC yielded fastidious bacteria from marine samples such as Acidobacteriota, Epsilonproteobacteria, Oligoflexia, and Verrucomicrobiota. Furthermore, 62% of the isolated strains were potential new species, whereas only 10% were novel species from SDP. From soil samples, isolates belonging to Acidobacteriota and Armatimonadota (which are known as rare species among identified isolates) were exclusively isolated by NCFLC. Colony formation capabilities of isolates cultivated by NCFLC were tested using solid agar plates, among which approximately one-third of the isolates were non-colony-forming, approximately half-formed micro-colonies, and only a minority could form ordinary size colonies. This indicates that the majority of the strains cultivated by NCFLC were previously uncultured microbial species unavailable using the SDP method. The NCFCL method described here can serve as a new approach to accessing the hidden microbial dark matter.
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Affiliation(s)
- Eun-Young Seo
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, China
- Ningbo Institute of Marine Medicine, Peking University, Ningbo, China
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashihiroshima, Japan
| | - Dawoon Jung
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, China
- Ningbo Institute of Marine Medicine, Peking University, Ningbo, China
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashihiroshima, Japan
| | - Slava S. Epstein
- Department of Biology, Northeastern University, Boston, MA, United States
| | - Weiyan Zhang
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, China
| | - Jeffrey S. Owen
- Department of Environmental Science, Hankuk University of Foreign Studies, Yongin, Republic of Korea
| | - Hiroaki Baba
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Akina Yamamoto
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Mifuyu Harada
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Yutaka Nakashimada
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashihiroshima, Japan
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Setsu Kato
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashihiroshima, Japan
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Yoshiteru Aoi
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashihiroshima, Japan
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
| | - Shan He
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, China
- Ningbo Institute of Marine Medicine, Peking University, Ningbo, China
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Microbial community structure and exploration of bioremediation enzymes: functional metagenomics insight into Arabian Sea sediments. Mol Genet Genomics 2023; 298:627-651. [PMID: 36933058 DOI: 10.1007/s00438-023-01995-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 01/28/2023] [Indexed: 03/19/2023]
Abstract
Deep-sea sediments provide important information on oceanic biogeochemical processes mediated by the microbiome and their functional roles which could be unravelled using genomic tools. The present study aimed to delineate microbial taxonomic and functional profiles from Arabian Sea sediment samples through whole metagenome sequencing using Nanopore technology. Arabian Sea is considered as a major microbial reservoir with significant bio-prospecting potential which needs to be explored extensively using recent advances in genomics. Assembly, co-assembly, and binning methods were used to predict Metagenome Assembled Genomes (MAGs) which were further characterized by their completeness and heterogeneity. Nanopore sequencing of Arabian Sea sediment samples generated around 1.73 tera basepairs of data. Proteobacteria (78.32%) was found to be the most dominant phylum followed by Bacteroidetes (9.55%) and Actinobacteria (2.14%) in the sediment metagenome. Further, 35 MAGs from assembled and 38 MAGs of co-assembled reads were generated from long-read sequence dataset with major representations from the genera Marinobacter, Kangiella, and Porticoccus. RemeDB analysis revealed a high representation of pollutant-degrading enzymes involved in hydrocarbon, plastic and dye degradation. Validation of enzymes with long nanopore reads using BlastX resulted in better characterization of complete gene signatures involved in hydrocarbon (6-monooxygenase and 4-hydroxyacetophenone monooxygenase) and dye degradation (Arylsulfatase). Enhancing the cultivability of deep-sea microbes predicted from the uncultured WGS approaches by I-tip method resulted in isolation of facultative extremophiles. This study presents a comprehensive insight into the taxonomic and functional profiles of Arabian Sea sediments, indicating a potential hotspot for bioprospection.
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Rodrigues CJC, de Carvalho CCCR. Marine Bioprospecting, Biocatalysis and Process Development. Microorganisms 2022; 10:1965. [PMID: 36296241 PMCID: PMC9610463 DOI: 10.3390/microorganisms10101965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/22/2022] [Accepted: 09/30/2022] [Indexed: 11/22/2022] Open
Abstract
Oceans possess tremendous diversity in microbial life. The enzymatic machinery that marine bacteria present is the result of extensive evolution to assist cell survival under the harsh and continuously changing conditions found in the marine environment. Several bacterial cells and enzymes are already used at an industrial scale, but novel biocatalysts are still needed for sustainable industrial applications, with benefits for both public health and the environment. Metagenomic techniques have enabled the discovery of novel biocatalysts, biosynthetic pathways, and microbial identification without their cultivation. However, a key stage for application of novel biocatalysts is the need for rapid evaluation of the feasibility of the bioprocess. Cultivation of not-yet-cultured bacteria is challenging and requires new methodologies to enable growth of the bacteria present in collected environmental samples, but, once a bacterium is isolated, its enzyme activities are easily measured. High-throughput screening techniques have also been used successfully, and innovative in vitro screening platforms to rapidly identify relevant enzymatic activities continue to improve. Small-scale approaches and process integration could improve the study and development of new bioprocesses to produce commercially interesting products. In this work, the latest studies related to (i) the growth of marine bacteria under laboratorial conditions, (ii) screening techniques for bioprospecting, and (iii) bioprocess development using microreactors and miniaturized systems are reviewed and discussed.
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Affiliation(s)
- Carlos J. C. Rodrigues
- Department of Bioengineering, iBB—Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
- Associate Laboratory i4HB—Institute for Health and Bioeconomy, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
| | - Carla C. C. R. de Carvalho
- Department of Bioengineering, iBB—Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
- Associate Laboratory i4HB—Institute for Health and Bioeconomy, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal
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Bergsten P, Vannier P, Frion J, Mougeolle A, Marteinsson VÞ. Culturable Bacterial Diversity from the Basaltic Subsurface of the Young Volcanic Island of Surtsey, Iceland. Microorganisms 2022; 10:1177. [PMID: 35744695 PMCID: PMC9229223 DOI: 10.3390/microorganisms10061177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 06/02/2022] [Accepted: 06/06/2022] [Indexed: 11/16/2022] Open
Abstract
The oceanic crust is the world's largest and least explored biosphere on Earth. The basaltic subsurface of Surtsey island in Iceland represents an analog of the warm and newly formed-oceanic crust and offers a great opportunity for discovering novel microorganisms. In this study, we collected borehole fluids, drill cores, and fumarole samples to evaluate the culturable bacterial diversity from the subsurface of the island. Enrichment cultures were performed using different conditions, media and temperatures. A total of 195 bacterial isolates were successfully cultivated, purified, and identified based on MALDI-TOF MS analysis and by 16S rRNA gene sequencing. Six different clades belonging to Firmicutes (40%), Gammaproteobacteria (28.7%), Actinobacteriota (22%), Bacteroidota (4.1%), Alphaproteobacteria (3%), and Deinococcota (2%) were identified. Bacillus (13.3%) was the major genus, followed by Geobacillus (12.33%), Enterobacter (9.23%), Pseudomonas (6.15%), and Halomonas (5.64%). More than 13% of the cultured strains potentially represent novel species based on partial 16S rRNA gene sequences. Phylogenetic analyses revealed that the isolated strains were closely related to species previously detected in soil, seawater, and hydrothermal active sites. The 16S rRNA gene sequences of the strains were aligned against Amplicon Sequence Variants (ASVs) from the previously published 16S rRNA gene amplicon sequence datasets obtained from the same samples. Compared with the culture-independent community composition, only 5 out of 49 phyla were cultivated. However, those five phyla accounted for more than 80% of the ASVs. Only 121 out of a total of 5642 distinct ASVs were culturable (≥98.65% sequence similarity), representing less than 2.15% of the ASVs detected in the amplicon dataset. Here, we support that the subsurface of Surtsey volcano hosts diverse and active microbial communities and that both culture-dependent and -independent methods are essential to improving our insight into such an extreme and complex volcanic environment.
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Affiliation(s)
- Pauline Bergsten
- Matís, Exploration and Utilization of Genetic Resources, 113 Reykjavík, Iceland; (P.B.); (P.V.); (J.F.); (A.M.)
- Faculty of Life and Environmental Sciences, University of Iceland, 102 Reykjavík, Iceland
| | - Pauline Vannier
- Matís, Exploration and Utilization of Genetic Resources, 113 Reykjavík, Iceland; (P.B.); (P.V.); (J.F.); (A.M.)
| | - Julie Frion
- Matís, Exploration and Utilization of Genetic Resources, 113 Reykjavík, Iceland; (P.B.); (P.V.); (J.F.); (A.M.)
| | - Alan Mougeolle
- Matís, Exploration and Utilization of Genetic Resources, 113 Reykjavík, Iceland; (P.B.); (P.V.); (J.F.); (A.M.)
| | - Viggó Þór Marteinsson
- Matís, Exploration and Utilization of Genetic Resources, 113 Reykjavík, Iceland; (P.B.); (P.V.); (J.F.); (A.M.)
- Faculty of Food Science and Nutrition, University of Iceland, 102 Reykjavík, Iceland
- Agricultural University of Iceland, 112 Reykjavík, Iceland
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9
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Anteneh YS, Yang Q, Brown MH, Franco CMM. Factors affecting the isolation and diversity of marine sponge-associated bacteria. Appl Microbiol Biotechnol 2022; 106:1729-1744. [PMID: 35103809 PMCID: PMC8882111 DOI: 10.1007/s00253-022-11791-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 01/13/2022] [Accepted: 01/17/2022] [Indexed: 12/24/2022]
Abstract
Marine sponges are an ideal source for isolating as yet undiscovered microorganisms with some sponges having about 50% of their biomass composed of microbial symbionts. This study used a variety of approaches to investigate the culturable diversity of the sponge-associated bacterial community from samples collected from the South Australian marine environment. Twelve sponge samples were selected from two sites and their bacterial population cultivated using seven different agar media at two temperatures and three oxygen levels over 3 months. These isolates were identified using microscopic, macroscopic, and 16S rRNA gene analysis. A total of 1234 bacterial colonies were isolated which consisted of four phyla: Actinobacteria, Firmicutes, Proteobacteria, and Bacteroidetes, containing 21 genera. The diversity of the bacterial population was demonstrated to be influenced by the type of isolation medium, length of the incubation period and temperature, sponge type, and oxygen level. The findings of this study showed that marine sponges of South Australia can yield considerable bacterial culturable diversity if a comprehensive isolation strategy is implemented. Two sponges, with the highest and the lowest diversity of culturable isolates, were examined using next-generation sequencing to better profile the bacterial population. A marked difference in terms of phyla and genera was observed using culture-based and culture-independent approaches. This observed variation displays the importance of utilizing both methods to reflect a more complete picture of the microbial population of marine sponges. KEY POINTS: Improved bacterial diversity due to long incubations, 2 temperatures, and 3 oxygen levels. Isolates identified by morphology, restriction digests, and 16S rRNA gene sequencing. At least 70% of culturable genera were not revealed by NGS methods.
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Affiliation(s)
- Yitayal S Anteneh
- Medical Biotechnology, College of Medicine and Public Health, Flinders University, Bedford Park, SA, 5042, Australia
- Department of Medical Microbiology, College of Medicine, Addis Ababa University, Addis Ababa, Ethiopia
- Centre for Marine Bioproducts Development, College of Medicine and Public Health, Flinders University, Bedford Park, SA, 5042, Australia
| | - Qi Yang
- Centre for Marine Bioproducts Development, College of Medicine and Public Health, Flinders University, Bedford Park, SA, 5042, Australia
- Center for Marine Drugs, State Key Laboratory of Oncogene and Related Genes, Department of Pharmacy, School of Medicine, Renji Hospital, Shanghai Jiao Tong University, Shanghai, 200127, China
| | - Melissa H Brown
- College of Science and Engineering, Flinders University, Bedford Park, SA, 5042, Australia
| | - Christopher M M Franco
- Medical Biotechnology, College of Medicine and Public Health, Flinders University, Bedford Park, SA, 5042, Australia.
- Centre for Marine Bioproducts Development, College of Medicine and Public Health, Flinders University, Bedford Park, SA, 5042, Australia.
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