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Gregson BH, Bani A, Steinfield L, Holt D, Whitby C. Anaerobes and methanogens dominate the microbial communities in water harvesting ponds used by Kenyan rural smallholder farmers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 819:153040. [PMID: 35026246 DOI: 10.1016/j.scitotenv.2022.153040] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 01/06/2022] [Accepted: 01/06/2022] [Indexed: 06/14/2023]
Abstract
Many rural smallholder farmers in Kenya use water-harvesting ponds, to collect rainwater, as sustainable sources of water for domestic and agricultural purposes. There is currently limited information regarding the microbial ecology in these ponds. Here, we used High Throughput Sequencing (HTS) to characterize the microorganisms present (including potential pathogens and indicator species) alongside ion chromatography to measure water chemistry (anion and cation concentration). Fluoride and magnesium concentration were the strongest predictor variables of the microbial community. Obligately or facultatively anaerobic bacterial genera (e.g. Spirochaeta and Opitutus) were abundant within the bacterial community, whilst Woesearchaeota and methanogens dominated the archaeal community. This suggests the water in the ponds is hypoxic or anoxic, and if used for irrigation, may potentially impact crop yield and viability. In addition, the opportunistic pathogen non-tuberculous mycobacteria (NTM), Mycobacterium fortuitum was found, comprising >1% of the bacterial community, suggesting a potential human health risk. Here we suggest low-cost changes to pond management, to improve or ameliorate pond anoxia and remove pathogens to benefit the livelihoods and welfare of these farms. This study also shows the applicability of HTS to broadly screen the microbial communities, assess water quality, and identify potentially pathogenic groups.
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Affiliation(s)
- Benjamin H Gregson
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | - Alessia Bani
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK
| | | | - Diane Holt
- Center for Enterprise and Entrepreneurship, Leeds University Business School, Leeds LS2 9JT, UK
| | - Corinne Whitby
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, UK.
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2
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Trubl G, Jang HB, Roux S, Emerson JB, Solonenko N, Vik DR, Solden L, Ellenbogen J, Runyon AT, Bolduc B, Woodcroft BJ, Saleska SR, Tyson GW, Wrighton KC, Sullivan MB, Rich VI. Soil Viruses Are Underexplored Players in Ecosystem Carbon Processing. mSystems 2018; 3:e00076-18. [PMID: 30320215 PMCID: PMC6172770 DOI: 10.1128/msystems.00076-18] [Citation(s) in RCA: 137] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Accepted: 08/24/2018] [Indexed: 01/10/2023] Open
Abstract
Rapidly thawing permafrost harbors ∼30 to 50% of global soil carbon, and the fate of this carbon remains unknown. Microorganisms will play a central role in its fate, and their viruses could modulate that impact via induced mortality and metabolic controls. Because of the challenges of recovering viruses from soils, little is known about soil viruses or their role(s) in microbial biogeochemical cycling. Here, we describe 53 viral populations (viral operational taxonomic units [vOTUs]) recovered from seven quantitatively derived (i.e., not multiple-displacement-amplified) viral-particle metagenomes (viromes) along a permafrost thaw gradient at the Stordalen Mire field site in northern Sweden. Only 15% of these vOTUs had genetic similarity to publicly available viruses in the RefSeq database, and ∼30% of the genes could be annotated, supporting the concept of soils as reservoirs of substantial undescribed viral genetic diversity. The vOTUs exhibited distinct ecology, with different distributions along the thaw gradient habitats, and a shift from soil-virus-like assemblages in the dry palsas to aquatic-virus-like assemblages in the inundated fen. Seventeen vOTUs were linked to microbial hosts (in silico), implicating viruses in infecting abundant microbial lineages from Acidobacteria, Verrucomicrobia, and Deltaproteobacteria, including those encoding key biogeochemical functions such as organic matter degradation. Thirty auxiliary metabolic genes (AMGs) were identified and suggested virus-mediated modulation of central carbon metabolism, soil organic matter degradation, polysaccharide binding, and regulation of sporulation. Together, these findings suggest that these soil viruses have distinct ecology, impact host-mediated biogeochemistry, and likely impact ecosystem function in the rapidly changing Arctic. IMPORTANCE This work is part of a 10-year project to examine thawing permafrost peatlands and is the first virome-particle-based approach to characterize viruses in these systems. This method yielded >2-fold-more viral populations (vOTUs) per gigabase of metagenome than vOTUs derived from bulk-soil metagenomes from the same site (J. B. Emerson, S. Roux, J. R. Brum, B. Bolduc, et al., Nat Microbiol 3:870-880, 2018, https://doi.org/10.1038/s41564-018-0190-y). We compared the ecology of the recovered vOTUs along a permafrost thaw gradient and found (i) habitat specificity, (ii) a shift in viral community identity from soil-like to aquatic-like viruses, (iii) infection of dominant microbial hosts, and (iv) carriage of host metabolic genes. These vOTUs can impact ecosystem carbon processing via top-down (inferred from lysing dominant microbial hosts) and bottom-up (inferred from carriage of auxiliary metabolic genes) controls. This work serves as a foundation which future studies can build upon to increase our understanding of the soil virosphere and how viruses affect soil ecosystem services.
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Affiliation(s)
- Gareth Trubl
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Ho Bin Jang
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Simon Roux
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Joanne B. Emerson
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Natalie Solonenko
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Dean R. Vik
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Lindsey Solden
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Jared Ellenbogen
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | | | - Benjamin Bolduc
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Ben J. Woodcroft
- Australian Centre for Ecogenomics, The University of Queensland, St. Lucia, Queensland, Australia
| | - Scott R. Saleska
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona, USA
| | - Gene W. Tyson
- Australian Centre for Ecogenomics, The University of Queensland, St. Lucia, Queensland, Australia
| | - Kelly C. Wrighton
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Matthew B. Sullivan
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
- Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, Columbus, Ohio, USA
| | - Virginia I. Rich
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
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Yan W, Ma H, Shi G, Li Y, Sun B, Xiao X, Zhang Y. Independent Shifts of Abundant and Rare Bacterial Populations across East Antarctica Glacial Foreland. Front Microbiol 2017; 8:1534. [PMID: 28848537 PMCID: PMC5554324 DOI: 10.3389/fmicb.2017.01534] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Accepted: 07/28/2017] [Indexed: 11/13/2022] Open
Abstract
Glacial forelands are extremely sensitive to temperature changes and are therefore appropriate places to explore the development of microbial communities in response to climate-driven deglaciation. In this study, we investigated the bacterial communities that developed at the initial stage of deglaciation using space-for-time substitution in the foreland of an ice sheet in Larsemann Hills. A series of soil samples across the glacial foreland were deeply sequenced with 16S rRNA gene amplicon sequencing to determine the bacterial community, including both abundant bacteria, which contribute more to geobiochemistry, and rare bacteria, which serve as a seed bank for diversity. Our results show that abundant bacterial communities were more sensitive to changing conditions in the early stages of deglaciation than rare community members. Moreover, among the environmental parameters tested, which included total organic carbon, pH, and moisture of the soils, ice thickness was the most influential factor affecting the community structure of abundant bacteria. These results show the different effects of abundant and rare bacteria on community shifts and highlight ice thickness as the primary factor affecting the bacterial community in the early stages of deglaciation. The response of microbial community to climate change can be predicted with more certainty in this polar region.
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Affiliation(s)
- Wenkai Yan
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong UniversityShanghai, China
| | - Hongmei Ma
- SOA Key Laboratory for Polar Science, Polar Research Institute of ChinaShanghai, China
| | - Guitao Shi
- SOA Key Laboratory for Polar Science, Polar Research Institute of ChinaShanghai, China
| | - Yuansheng Li
- SOA Key Laboratory for Polar Science, Polar Research Institute of ChinaShanghai, China
| | - Bo Sun
- SOA Key Laboratory for Polar Science, Polar Research Institute of ChinaShanghai, China
| | - Xiang Xiao
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong UniversityShanghai, China
| | - Yu Zhang
- State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong UniversityShanghai, China.,Institute of Oceanography, Shanghai Jiao Tong UniversityShanghai, China
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Verrucomicrobial community structure and abundance as indicators for changes in chemical factors linked to soil fertility. Antonie van Leeuwenhoek 2015; 108:741-52. [PMID: 26184407 PMCID: PMC4525199 DOI: 10.1007/s10482-015-0530-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 07/07/2015] [Indexed: 12/18/2022]
Abstract
Here we show that verrucomicrobial community structure and abundance are extremely sensitive to changes in chemical factors linked to soil fertility. Terminal restriction fragment length polymorphism fingerprint and real-time quantitative PCR assay were used to analyze changes in verrucomicrobial communities associated with contrasting soil nutrient conditions in tropical regions. In case study Model I (“Slash-and-burn deforestation”) the verrucomicrobial community structures revealed disparate patterns in nutrient-enriched soils after slash-and-burn deforestation and natural nutrient-poor soils under an adjacent primary forest in the Amazonia (R = 0.819, P = 0.002). The relative proportion of Verrucomicrobia declined in response to increased soil fertility after slash-and-burn deforestation, accounting on average, for 4 and 2 % of the total bacterial signal, in natural nutrient-poor forest soils and nutrient-enriched deforested soils, respectively. In case study Model II (“Management practices for sugarcane”) disparate patterns were revealed in sugarcane rhizosphere sampled on optimal and deficient soil fertility for sugarcane (R = 0.786, P = 0.002). Verrucomicrobial community abundance in sugarcane rhizosphere was negatively correlated with soil fertility, accounting for 2 and 5 % of the total bacterial signal, under optimal and deficient soil fertility conditions for sugarcane, respectively. In nutrient-enriched soils, verrucomicrobial community structures were related to soil factors linked to soil fertility, such as total nitrogen, phosphorus, potassium and sum of bases, i.e., the sum of calcium, magnesium and potassium contents. We conclude that community structure and abundance represent important ecological aspects in soil verrucomicrobial communities for tracking the changes in chemical factors linked to soil fertility under tropical environmental conditions.
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Kanengoni AT, Chimonyo M, Tasara T, Cormican P, Chapwanya A, Ndimba BK, Dzama K. A comparison of faecal microbial populations of South African Windsnyer-type indigenous pigs (SAWIPs) and Large White × Landrace (LW × LR) crosses fed diets containing ensiled maize cobs. FEMS Microbiol Lett 2015; 362:fnv100. [PMID: 26091682 DOI: 10.1093/femsle/fnv100] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/15/2015] [Indexed: 12/26/2022] Open
Abstract
Faecal microbial communities in South African Windsnyer-type indigenous pigs (SAWIPs) and Large White × Landrace (LW × LR) crosses were investigated using high-throughput sequencing of the 16S rDNA genes. The faecal microbial communities in LW × LR crosses and SAWIPs fed control (CON) and high maize cob (HMC) diets were evaluated through parallel sequencing of 16S rDNA genes. Butrivibrio, Faecalibacterium and Desulfovibrio, although present in LW × LR pigs, were absent from the SAWIP microbial community. Bacteroides, Succiniclasticum, Peptococcus and Akkermansia were found in SAWIPs but not in LW × LR crosses. The ratios of Bacteroidia to Clostridia on the CON and HMC diets were similar (0.37 versus 0.39) in SAWIPs but different (0.24 versus 0.1) in LW × LR crosses. The faecal microbial profiles determined were different between the LW × LR and SAWIP breeds but not between pigs fed the CON and HMC diets. The composition of faecal bacterial communities in SAWIPs was determined for the first time. The differences in microbial communities detected may explain the enhanced ability of SAWIPs to digest fibrous diets compared with the LW × LR crosses.
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Affiliation(s)
- Arnold T Kanengoni
- Agricultural Research Council-Animal Production Institute, Private Bag X2, Irene, 0062, South Africa Department of Animal Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
| | - Michael Chimonyo
- Discipline of Animal & Poultry Science, University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermaritzburg, 3209, South Africa
| | - Taurai Tasara
- Institute for Food Safety and Hygiene, Vetsuisse Faculty University of Zurich, Switzerland
| | - Paul Cormican
- Animal & Grassland Research and Innovation Centre, Teagasc, Grange, Co. Meath, Ireland
| | - Aspinas Chapwanya
- Ross University School of Veterinary Medicine, Department of Clinical Sciences, Box 34, Basseterre, St Kitts and Nevis
| | - Bongani K Ndimba
- Agricultural Research Council, Proteomics Research and Services Unit, Helshoogte Road, Infruitech. Nietvoorbij Institute, Stellenbosch 7599, South Africa Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville, Cape Town, 7535, South Africa
| | - Kennedy Dzama
- Department of Animal Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa
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Bergmann GT, Bates ST, Eilers KG, Lauber CL, Caporaso JG, Walters WA, Knight R, Fierer N. The under-recognized dominance of Verrucomicrobia in soil bacterial communities. SOIL BIOLOGY & BIOCHEMISTRY 2011; 43:1450-1455. [PMID: 22267877 PMCID: PMC3260529 DOI: 10.1016/j.soilbio.2011.03.012] [Citation(s) in RCA: 357] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Verrucomicrobia are ubiquitous in soil, but members of this bacterial phylum are thought to be present at low frequency in soil, with few studies focusing specifically on verrucomicrobial abundance, diversity, and distribution. Here we used barcoded pyrosequencing to analyze verrucomicrobial communities in surface soils collected across a range of biomes in Antarctica, Europe, and the Americas (112 samples), as well as soils collected from pits dug in a montane coniferous forest (69 samples). Data collected from surface horizons indicate that Verrucomicrobia average 23% of bacterial sequences, making them far more abundant than had been estimated. We show that this underestimation is likely due to primer bias, as many of the commonly used PCR primers appear to exclude verrucomicrobial 16S rRNA genes during amplification. Verrucomicrobia were detected in 180 out of 181 soils examined, with members of the class Spartobacteria dominating verrucomicrobial communities in nearly all biomes and soil depths. The relative abundance of Verrucomicrobia was highest in grasslands and in subsurface soil horizons, where they were often the dominant bacterial phylum. Although their ecology remains poorly understood, Verrucomicrobia appear to be dominant in many soil bacterial communities across the globe, making additional research on their ecology clearly necessary.
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Affiliation(s)
- Gaddy T. Bergmann
- Cooperative Institute for Research in Environmental Sciences, University of Colorado at Boulder, Campus Box 216, Boulder, Colorado 80309-0216, USA
- Department of Ecology and Evolutionary Biology, University of Colorado at Boulder, Campus Box 334, Boulder, Colorado 80309-0334, USA
| | - Scott T. Bates
- Cooperative Institute for Research in Environmental Sciences, University of Colorado at Boulder, Campus Box 216, Boulder, Colorado 80309-0216, USA
- Department of Ecology and Evolutionary Biology, University of Colorado at Boulder, Campus Box 334, Boulder, Colorado 80309-0334, USA
| | - Kathryn G. Eilers
- Cooperative Institute for Research in Environmental Sciences, University of Colorado at Boulder, Campus Box 216, Boulder, Colorado 80309-0216, USA
- Department of Ecology and Evolutionary Biology, University of Colorado at Boulder, Campus Box 334, Boulder, Colorado 80309-0334, USA
| | - Christian L. Lauber
- Cooperative Institute for Research in Environmental Sciences, University of Colorado at Boulder, Campus Box 216, Boulder, Colorado 80309-0216, USA
- Department of Ecology and Evolutionary Biology, University of Colorado at Boulder, Campus Box 334, Boulder, Colorado 80309-0334, USA
| | - J. Gregory Caporaso
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, Campus Box 215, Boulder, Colorado 80309-0215, USA
| | - William A. Walters
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado at Boulder, Campus Box 347, Boulder, Colorado 80309-0347, USA
| | - Rob Knight
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, Campus Box 215, Boulder, Colorado 80309-0215, USA
- Howard Hughes Medical Institute, 4000 Jones Bridge Road, Chevy Chase, MD 20815-6789
| | - Noah Fierer
- Cooperative Institute for Research in Environmental Sciences, University of Colorado at Boulder, Campus Box 216, Boulder, Colorado 80309-0216, USA
- Department of Ecology and Evolutionary Biology, University of Colorado at Boulder, Campus Box 334, Boulder, Colorado 80309-0334, USA
- Corresponding author: Dr. Noah Fierer Assistant professor University of Colorado at Boulder Department of Ecology and Evolutionary Biology CIRES Box 216 UCB Boulder, CO 80309-0216, USA Office: 303-492-5615 Lab: 303-492-2099 Fax: 303-492-1149
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Genome sequence of the verrucomicrobium Opitutus terrae PB90-1, an abundant inhabitant of rice paddy soil ecosystems. J Bacteriol 2011; 193:2367-8. [PMID: 21398538 DOI: 10.1128/jb.00228-11] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacteria of the deeply branching phylum Verrucomicrobia are rarely cultured yet commonly detected in metagenomic libraries from aquatic, terrestrial, and intestinal environments. We have sequenced the genome of Opitutus terrae PB90-1, a fermentative anaerobe within this phylum, isolated from rice paddy soil and capable of propionate production from plant-derived polysaccharides.
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Janssen PH. Propanol as an end product of threonine fermentation. Arch Microbiol 2004; 182:482-6. [PMID: 15455192 DOI: 10.1007/s00203-004-0732-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2004] [Revised: 08/30/2004] [Accepted: 09/07/2004] [Indexed: 10/26/2022]
Abstract
Clostridium sp. strain 17cr1 was able to ferment L-threonine to propionate and propanol. Electrons arising in the oxidation of 2-oxobutyrate to propionyl-CoA were apparently used in reductive pathway leading to propanol formation. Part of the propionyl-CoA was used to form propionate in an ATP-forming pathway via a propionate kinase, so that the final ATP yield was 0.5 mol per mol of L-threonine metabolised. Other growth substrates were fermented mainly to acetate and butyrate, and the reductive formation of butyrate, from 2 mol of acetyl-CoA or from crotonate or 3-hydroxybutyrate, was the main route for recycling reduced electron carriers arising during oxidative pathways for most substrates.
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Affiliation(s)
- Peter H Janssen
- Department of Microbiology and Immunology, University of Melbourne, Victoria 3010, Australia
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Janssen PH, Hugenholtz P. Fermentation of glycolate by a pure culture of a strictly anaerobic gram-positive bacterium belonging to the family Lachnospiraceae. Arch Microbiol 2003; 179:321-8. [PMID: 12658332 DOI: 10.1007/s00203-003-0528-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2002] [Revised: 01/27/2003] [Accepted: 01/28/2003] [Indexed: 11/30/2022]
Abstract
The component bacteria of a three-membered mixed culture able to ferment glycolate to acetate, propionate and CO(2) were isolated in pure culture. All three strains were strict anaerobes that, on the basis of comparative 16S rRNA gene sequence analysis, belonged to the order Clostridiales in the phylum Firmicutes (low G+C gram-positive bacteria). Two of the strains were not involved in glycolate metabolism. The third, the glycolate-fermenting strain 19gly4 (DSM 11261), was related to members of the family Lachnospiraceae. The cells of strain 19gly4 were oval- to lemon-shaped, 0.85 microm long and 0.65 microm in diameter, occurring singly, in pairs, or in chains of up to 30 cells. Strain 19gly4 fermented glycolate or fumarate to acetate, succinate, and CO(2). Hydrogen was not formed, and strain 19gly4 was able to grow on glycolate in pure culture without any syntrophic hydrogen transfer and without the use of an external electron acceptor. There was no evidence for homoacetogenic metabolism. This bacterium therefore differs in metabolism from previously reported glycolate-utilising anaerobes.
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Affiliation(s)
- Peter H Janssen
- Department of Microbiology and Immunology, University of Melbourne, 3010, Victoria, Australia.
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Chin KJ, Janssen PH. Propionate formation by Opitutus terrae in pure culture and in mixed culture with a hydrogenotrophic methanogen and implications for carbon fluxes in anoxic rice paddy soil. Appl Environ Microbiol 2002; 68:2089-92. [PMID: 11916740 PMCID: PMC123890 DOI: 10.1128/aem.68.4.2089-2092.2002] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2001] [Accepted: 01/11/2002] [Indexed: 11/20/2022] Open
Abstract
Propionate-forming bacteria seem to be abundant in anoxic rice paddy soil, but biogeochemical investigations show that propionate is not a correspondingly important intermediate in carbon flux in this system. Mixed cultures of Opitutus terrae strain PB90-1, a representative propionate-producing bacterium from rice paddy soil, and the hydrogenotrophic Methanospirillum hungatei strain SK maintained hydrogen partial pressures similar to those in the soil. The associated shift away from propionate formation observed in these cultures helps to reconcile the disparity between microbiological and biogeochemical studies.
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Affiliation(s)
- Kuk-Jeong Chin
- Max-Planck-Institut für Terrestrische Mikrobiologie, D-35043 Marburg, Germany
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