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Aepfler RF, Bühring SI, Elvert M. Substrate characteristic bacterial fatty acid production based on amino acid assimilation and transformation in marine sediments. FEMS Microbiol Ecol 2019; 95:5555570. [PMID: 31504469 DOI: 10.1093/femsec/fiz131] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 08/23/2019] [Indexed: 01/25/2023] Open
Abstract
Polar lipid-derived fatty acids (PLFAs) and their stable carbon isotopes are frequently combined to characterize microbial populations involved in the degradation of organic matter, offering a link to biogeochemical processes and carbon sources used. However, PLFA patterns derive from multiple species and may be influenced by substrate types. Here, we investigated such dependencies by monitoring the transformation of position-specifically 13C-labeled amino acids (AAs) in coastal marine sediments dominated by heterotrophic bacteria. Alanine was assimilated into straight-chain FAs, while valine and leucine incorporation led to the characteristic production of even- and odd-numbered iso-series FAs. This suggests that identical microbial communities adjust lipid biosynthesis according to substrate availability. Transformation into precursor molecules for FA biosynthesis was manifested in increased 13C recoveries of the corresponding volatiles acetate, isobutyrate and isovalerate of up to 39.1%, much higher than for PLFAs (<0.9%). A significant fraction of 13C was found in dissolved inorganic carbon (up to 37.9%), while less was recovered in total organic carbon (up to 17.3%). We observed a clear discrimination against the carboxyl C, whereby C2 and C3 positions were preferentially incorporated into PLFAs. Therefore, position-specific labeling is an appropriate tool for reconstructing the metabolic fate of protein-derived AAs in marine environments.
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Affiliation(s)
- Rebecca F Aepfler
- Organic Geochemistry Group, MARUM-Center for Marine Environmental Sciences, University of Bremen, Leobener Strasse 8, 28359 Bremen, Germany.,Hydrothermal Geomicrobiology Group, MARUM-Center for Marine Environmental Sciences, University of Bremen, Leobener Strasse 13, 28359 Bremen, Germany
| | - Solveig I Bühring
- Hydrothermal Geomicrobiology Group, MARUM-Center for Marine Environmental Sciences, University of Bremen, Leobener Strasse 13, 28359 Bremen, Germany
| | - Marcus Elvert
- Organic Geochemistry Group, MARUM-Center for Marine Environmental Sciences, University of Bremen, Leobener Strasse 8, 28359 Bremen, Germany
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Dyksma S, Lenk S, Sawicka JE, Mußmann M. Uncultured Gammaproteobacteria and Desulfobacteraceae Account for Major Acetate Assimilation in a Coastal Marine Sediment. Front Microbiol 2018; 9:3124. [PMID: 30619197 PMCID: PMC6305295 DOI: 10.3389/fmicb.2018.03124] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 12/03/2018] [Indexed: 11/13/2022] Open
Abstract
Acetate is a key intermediate in anaerobic mineralization of organic matter in marine sediments. Its turnover is central to carbon cycling, however, the relative contribution of different microbial populations to acetate assimilation in marine sediments is unknown. To quantify acetate assimilation by in situ abundant bacterial populations, we incubated coastal marine sediments with 14C-labeled acetate and flow-sorted cells that had been labeled and identified by fluorescence in situ hybridization. Subsequently, scintillography determined the amount of 14C-acetate assimilated by distinct populations. This approach fostered a high-throughput quantification of acetate assimilation by phylogenetically identified populations. Acetate uptake was highest in the oxic-suboxic surface layer for all sorted bacterial populations, including deltaproteobacterial sulfate-reducing bacteria (SRB), which accounted for up to 32% of total bacterial acetate assimilation. We show that the family Desulfobulbaceae also assimilates acetate in marine sediments, while the more abundant Desulfobacteraceae dominated acetate assimilation despite lower uptake rates. Unexpectedly, members of Gammaproteobacteria accounted for the highest relative acetate assimilation in all sediment layers with up to 31–62% of total bacterial acetate uptake. We also show that acetate is used to build up storage compounds such as polyalkanoates. Together, our findings demonstrate that not only the usual suspects SRB but a diverse bacterial community may substantially contribute to acetate assimilation in marine sediments. This study highlights the importance of quantitative approaches to reveal the roles of distinct microbial populations in acetate turnover.
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Affiliation(s)
- Stefan Dyksma
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany.,Faculty of Technology, Microbiology - Biotechnology, University of Applied Sciences, Emden, Germany
| | - Sabine Lenk
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Joanna E Sawicka
- Department of Biogeochemistry, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Marc Mußmann
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany.,Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria
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Uhlik O, Leewis MC, Strejcek M, Musilova L, Mackova M, Leigh MB, Macek T. Stable isotope probing in the metagenomics era: a bridge towards improved bioremediation. Biotechnol Adv 2012; 31:154-65. [PMID: 23022353 DOI: 10.1016/j.biotechadv.2012.09.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Revised: 09/17/2012] [Accepted: 09/17/2012] [Indexed: 12/24/2022]
Abstract
Microbial biodegradation and biotransformation reactions are essential to most bioremediation processes, yet the specific organisms, genes, and mechanisms involved are often not well understood. Stable isotope probing (SIP) enables researchers to directly link microbial metabolic capability to phylogenetic and metagenomic information within a community context by tracking isotopically labeled substances into phylogenetically and functionally informative biomarkers. SIP is thus applicable as a tool for the identification of active members of the microbial community and associated genes integral to the community functional potential, such as biodegradative processes. The rapid evolution of SIP over the last decade and integration with metagenomics provide researchers with a much deeper insight into potential biodegradative genes, processes, and applications, thereby enabling an improved mechanistic understanding that can facilitate advances in the field of bioremediation.
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Affiliation(s)
- Ondrej Uhlik
- Institute of Chemical Technology Prague, Faculty of Food and Biochemical Technology, Department of Biochemistry and Microbiology, Technicka 3, 166 28 Prague, Czech Republic.
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Mayali X, Weber PK, Pett-Ridge J. Taxon-specific C/N relative use efficiency for amino acids in an estuarine community. FEMS Microbiol Ecol 2012; 83:402-12. [PMID: 22994392 DOI: 10.1111/j.1574-6941.12000.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 08/16/2012] [Accepted: 08/18/2012] [Indexed: 11/30/2022] Open
Abstract
Microbial activity plays a critical role in determining the nutrient status of an ecosystem (i.e. N or C limitation). While the balance of C/N assimilation has been measured at the whole community scale, quantitative detection of N and C assimilation from a single substrate at the scale of individual taxa has not been carried out. We recently developed Chip-SIP, a microarray and NanoSIMS-based method for linking microbial phylogeny and function that allows simultaneous measurement of (15)N and (13)C incorporation. Here, we measured the relative incorporation of C and N from dual-labeled substrates by individual microbial taxa in bottle incubations of samples collected from an estuary. Incubation times < 24 h were sufficient to successfully detect active microbes incorporating (15)N ammonium. In subsequent experiments, we used the incorporation of labeled amino acids (AAs) as a proxy for heterotrophic activity and showed different levels of incorporation among different taxonomic groups. Taxon-specific differences in the net incorporation of AA-derived C and N indicate that the C/N relative use efficiency ranged from 0.8 to 1.4, where 1 reflects stoichiometric incorporation of C and N. Our results revealed that microbial organic matter processing is affected by taxon-specific physiological diversity, both in terms of general activity levels and in the ratio of assimilated C/N.
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Affiliation(s)
- Xavier Mayali
- Chemical Science Division, Lawrence Livermore National Laboratory, Livermore, CA, USA.
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5
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Key players and team play: anaerobic microbial communities in hydrocarbon-contaminated aquifers. Appl Microbiol Biotechnol 2012; 94:851-73. [PMID: 22476263 DOI: 10.1007/s00253-012-4025-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2012] [Revised: 03/13/2012] [Accepted: 03/14/2012] [Indexed: 02/06/2023]
Abstract
Biodegradation of anthropogenic pollutants in shallow aquifers is an important microbial ecosystem service which is mainly brought about by indigenous anaerobic microorganisms. For the management of contaminated sites, risk assessment and control of natural attenuation, the assessment of in situ biodegradation and the underlying microbial processes is essential. The development of novel molecular methods, "omics" approaches, and high-throughput techniques has revealed new insight into complex microbial communities and their functions in anoxic environmental systems. This review summarizes recent advances in the application of molecular methods to study anaerobic microbial communities in contaminated terrestrial subsurface ecosystems. We focus on current approaches to analyze composition, dynamics, and functional diversity of subsurface communities, to link identity to activity and metabolic function, and to identify the ecophysiological role of not yet cultured microbes and syntrophic consortia. We discuss recent molecular surveys of contaminated sites from an ecological viewpoint regarding degrader ecotypes, abiotic factors shaping anaerobic communities, and biotic interactions underpinning the importance of microbial cooperation for microbial ecosystem services such as contaminant degradation.
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Abed RMM. Detection and Capturing of (14)C Radioactively-Labeled Small Subunit rRNA from Mixed Microbial Communities of a Microbial Mat Using Magnetic Beads. Indian J Microbiol 2012; 52:88-93. [PMID: 23449550 PMCID: PMC3298593 DOI: 10.1007/s12088-011-0239-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Accepted: 10/13/2011] [Indexed: 10/16/2022] Open
Abstract
Carbon cycling in the hypersaline microbial mats from Chiprana Lake, Spain is primarily dependent on phototrophic microorganisms with the ability to fix CO2 into organics that can be further utilized by aerobic as well as anaerobic heterotrophic bacteria. Here, mat pieces were incubated in seawater amended with (14)C sodium bicarbonate and the incorporation of the radiocarbon in the small subunit ribosomal RNA (SSU rRNA) of mat organisms was followed using scintillation counter and autoradiography. Different domains of SSU rRNA were separated from the total RNA by means of streptavidin-coated magnetic beads and biotin-labeled oligonucleotide probes. The (14)C label was detected in isolated RNA by both scintillation counter and autoradiography, however the latter technique was less sensitive. Using scintillation counter, the radiolabel incorporation increased with time with a maximum rate of 0.18 Bq ng(-1) detected after 25 days. The bacterial SSU rRNA could be captured using the magnetic beads, however the hybridization efficiency was around 20%. The captured RNA was radioactively labeled, which could be mainly due to the fixation of radiocarbon by phototrophic organisms. In conclusion, the incubation of microbial mats in the presence of radiolabeled bicarbonate leads to the incorporation of the (14)C label into RNA molecules through photosynthesis and this label can be detected using scintillation counter. The used approach could be useful in studying the fate of fixed carbon and its uptake by other microorganisms in complex microbial mats, particularly when species-specific probes are used and the hybridization efficiency and RNA yield are further optimized.
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Affiliation(s)
- Raeid M. M. Abed
- Biology Department, College of Science, Sultan Qaboos University, P.O.Box 36, Al Khoud, 123 Muscat, Sultanate of Oman
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Musat N, Foster R, Vagner T, Adam B, Kuypers MMM. Detecting metabolic activities in single cells, with emphasis on nanoSIMS. FEMS Microbiol Rev 2012; 36:486-511. [DOI: 10.1111/j.1574-6976.2011.00303.x] [Citation(s) in RCA: 189] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Accepted: 08/22/2011] [Indexed: 11/30/2022] Open
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Use of stable isotopes to measure the metabolic activity of the human intestinal microbiota. Appl Environ Microbiol 2011; 77:8009-14. [PMID: 21948826 DOI: 10.1128/aem.05573-11] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The human intestinal microbiota is a complex biological system comprising a vast repertoire of microbes with considerable metabolic activity relevant to both bacterial growth and host health. Greater strides have been made in the analysis of microbial diversity than in the measurement of functional activity, particularly in vivo. Stable isotope probing offers a new approach by coupling measurements of metabolic activity with microbial identification. Using a low-enrichment labeling strategy in vitro, this study has identified metabolically active bacterial groups via magnetic-bead capture methodology and stable isotope ratio analysis. Using five probes (EUB338, Bac303, Bif164, EREC482, and Clep866), changes in the activities of key intestinal microbial groups were successfully measured by exploiting tracers of de novo RNA synthesis. Perturbation of the nutrient source with oligofructose generated changes in the activity of bifidobacteria as expected, but also in the Bacteroides-Prevotella group, the Eubacterium rectale-Clostridium coccoides group, and the Clostridium leptum subgroup. Changes in activity were also observed in response to the medium type. This study suggests that changes in the functional activity of the gut microbiota can be assessed using tracers of de novo nucleic acid synthesis combined with measurement of low isotopic enrichment in 16S rRNA. Such tracers potentially limit substrate bias because they are universally available to bacteria. This low-enrichment labeling approach does not depend on the commercial availability of specific labeled substrates and can be easily translated to in vivo probing experiments of the functional activity of the microbiota in the human gut.
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Webster G, Rinna J, Roussel EG, Fry JC, Weightman AJ, Parkes RJ. Prokaryotic functional diversity in different biogeochemical depth zones in tidal sediments of the Severn Estuary, UK, revealed by stable-isotope probing. FEMS Microbiol Ecol 2010; 72:179-97. [DOI: 10.1111/j.1574-6941.2010.00848.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Linking microbial community function to phylogeny of sulfate-reducing Deltaproteobacteria in marine sediments by combining stable isotope probing with magnetic-bead capture hybridization of 16S rRNA. Appl Environ Microbiol 2009; 75:4927-35. [PMID: 19502447 DOI: 10.1128/aem.00652-09] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We further developed the stable isotope probing, magnetic-bead capture method to make it applicable for linking microbial community function to phylogeny at the class and family levels. The main improvements were a substantial decrease in the protocol blank and an approximately 10-fold increase in the detection limit by using a micro-elemental analyzer coupled to isotope ratio mass spectrometry to determine (13)C labeling of isolated 16S rRNA. We demonstrated the method by studying substrate utilization by Desulfobacteraceae, a dominant group of complete oxidizing sulfate-reducing Deltaproteobacteria in marine sediments. Stable-isotope-labeled [(13)C]glucose, [(13)C]propionate, or [(13)C]acetate was fed into an anoxic intertidal sediment. We applied a nested set of three biotin-labeled oligonucleotide probes to capture Bacteria, Deltaproteobacteria, and finally Desulfobacteraceae rRNA by using hydrophobic streptavidin-coated paramagnetic beads. The target specificities of the probes were examined with pure cultures of target and nontarget species and by determining the phylogenetic composition of the captured sediment rRNA. The specificity of the final protocol was generally very good, as more than 90% of the captured 16S rRNA belonged to the target range of the probes. Our results indicated that Desulfobacteraceae were important consumers of propionate but not of glucose. However, the results for acetate utilization were less conclusive due to lower and more variable labeling levels in captured rRNA. The main advantage of the method in this study over other nucleic acid-based stable isotope probing methods is that (13)C labeling can be much lower, to the extent that delta(13)C ratios can be studied even at their natural abundances.
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Langenheder S, Prosser JI. Resource availability influences the diversity of a functional group of heterotrophic soil bacteria. Environ Microbiol 2008; 10:2245-56. [PMID: 18479445 DOI: 10.1111/j.1462-2920.2008.01647.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Resource availability is a key factor regulating biodiversity and ecosystem functioning, but the relationship between resource availability and diversity has only been rarely investigated in microbial communities. The aim of this study was to determine how diversity and community structure of a functional group of soil bacteria are influenced by resource concentration. To achieve this, we used soil microcosms to investigate degradation of benzoate, which served as a model compound, by soil bacterial communities. Microcosms were supplied with (13)C-labelled benzoate at four concentrations and RNA-stable isotope probing followed by molecular fingerprinting analysis of 16S rRNA genes was employed to identify bacteria able to assimilate benzoate at different concentrations. The composition of the benzoate degrader community differed at different concentrations and there was a significant decrease in taxa evenness at the highest substrate concentration. Active organisms could be grouped into generalists, occurring at all substrate concentrations, specialists, active at one particular benzoate concentration only, and taxa that were active at either the two lowest or two highest concentrations. The study comprises the first explicit demonstration that resource availability has an effect on the diversity of a functional group of heterotrophic soil bacteria.
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Affiliation(s)
- Silke Langenheder
- School of Biological Sciences, Department of Plant and Soil Science, University of Aberdeen, Scotland, UK.
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Linking microbial phylogeny to metabolic activity at the single-cell level by using enhanced element labeling-catalyzed reporter deposition fluorescence in situ hybridization (EL-FISH) and NanoSIMS. Appl Environ Microbiol 2008; 74:3143-50. [PMID: 18359832 DOI: 10.1128/aem.00191-08] [Citation(s) in RCA: 161] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To examine phylogenetic identity and metabolic activity of individual cells in complex microbial communities, we developed a method which combines rRNA-based in situ hybridization with stable isotope imaging based on nanometer-scale secondary-ion mass spectrometry (NanoSIMS). Fluorine or bromine atoms were introduced into cells via 16S rRNA-targeted probes, which enabled phylogenetic identification of individual cells by NanoSIMS imaging. To overcome the natural fluorine and bromine backgrounds, we modified the current catalyzed reporter deposition fluorescence in situ hybridization (FISH) technique by using halogen-containing fluorescently labeled tyramides as substrates for the enzymatic tyramide deposition. Thereby, we obtained an enhanced element labeling of microbial cells by FISH (EL-FISH). The relative cellular abundance of fluorine or bromine after EL-FISH exceeded natural background concentrations by up to 180-fold and allowed us to distinguish target from non-target cells in NanoSIMS fluorine or bromine images. The method was optimized on single cells of axenic Escherichia coli and Vibrio cholerae cultures. EL-FISH/NanoSIMS was then applied to study interrelationships in a dual-species consortium consisting of a filamentous cyanobacterium and a heterotrophic alphaproteobacterium. We also evaluated the method on complex microbial aggregates obtained from human oral biofilms. In both samples, we found evidence for metabolic interactions by visualizing the fate of substrates labeled with (13)C-carbon and (15)N-nitrogen, while individual cells were identified simultaneously by halogen labeling via EL-FISH. Our novel approach will facilitate further studies of the ecophysiology of known and uncultured microorganisms in complex environments and communities.
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Pearson A, Kraunz KS, Sessions AL, Dekas AE, Leavitt WD, Edwards KJ. Quantifying microbial utilization of petroleum hydrocarbons in salt marsh sediments by using the 13C content of bacterial rRNA. Appl Environ Microbiol 2008; 74:1157-66. [PMID: 18083852 PMCID: PMC2258585 DOI: 10.1128/aem.01014-07] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2007] [Accepted: 12/04/2007] [Indexed: 11/20/2022] Open
Abstract
Natural remediation of oil spills is catalyzed by complex microbial consortia. Here we took a whole-community approach to investigate bacterial incorporation of petroleum hydrocarbons from a simulated oil spill. We utilized the natural difference in carbon isotopic abundance between a salt marsh ecosystem supported by the 13C-enriched C4 grass Spartina alterniflora and 13C-depleted petroleum to monitor changes in the 13C content of biomass. Magnetic bead capture methods for selective recovery of bacterial RNA were used to monitor the 13C content of bacterial biomass during a 2-week experiment. The data show that by the end of the experiment, up to 26% of bacterial biomass was derived from consumption of the freshly spilled oil. The results contrast with the inertness of a nearby relict spill, which occurred in 1969 in West Falmouth, MA. Sequences of 16S rRNA genes from our experimental samples also were consistent with previous reports suggesting the importance of Gamma- and Deltaproteobacteria and Firmicutes in the remineralization of hydrocarbons. The magnetic bead capture approach makes it possible to quantify uptake of petroleum hydrocarbons by microbes in situ. Although employed here at the domain level, RNA capture procedures can be highly specific. The same strategy could be used with genus-level specificity, something which is not currently possible using the 13C content of biomarker lipids.
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Affiliation(s)
- Ann Pearson
- Department of Earth and Planetary Sciences, Harvard University, 20 Oxford St., Cambridge MA 02138, USA.
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Huang WE, Stoecker K, Griffiths R, Newbold L, Daims H, Whiteley AS, Wagner M. Raman-FISH: combining stable-isotope Raman spectroscopy and fluorescence in situ hybridization for the single cell analysis of identity and function. Environ Microbiol 2007; 9:1878-89. [PMID: 17635536 DOI: 10.1111/j.1462-2920.2007.01352.x] [Citation(s) in RCA: 209] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have coupled fluorescence in situ hybridization (FISH) with Raman microscopy for simultaneous cultivation-independent identification and determination of (13)C incorporation into microbial cells. Highly resolved Raman confocal spectra were generated for individual cells which were grown in minimal medium where the ratio of (13)C to (12)C content of the sole carbon source was incrementally varied. Cells which were (13)C-labelled through anabolic incorporation of the isotope exhibited key red-shifted spectral peaks, the calculated 'red shift ratio' (RSR) being highly correlated with the (13)C-content of the cells. Subsequently, Raman instrumentation and FISH protocols were optimized to allow combined epifluorescence and Raman imaging of Fluos, Cy3 and Cy5-labelled microbial populations at the single cell level. Cellular (13)C-content determinations exhibited good congruence between fresh cells and FISH hybridized cells indicating that spectral peaks, including phenylalanine resonance, which were used to determine (13)C-labelling, were preserved during fixation and hybridization. In order to demonstrate the suitability of this technology for structure-function analyses in complex microbial communities, Raman-FISH was deployed to show the importance of Pseudomonas populations during naphthalene degradation in groundwater microcosms. Raman-FISH extends and complements current technologies such as FISH-microautoradiography and stable isotope probing in that it can be applied at the resolution of single cells in complex communities, is quantitative if suitable calibrations are performed, can be used with stable isotopes and has analysis times of typically 1 min per cell.
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Affiliation(s)
- Wei E Huang
- Biodiversity and Ecosystem Function Group, Molecular Microbial Ecology Section, Centre for Ecology and Hydrology Oxford, Mansfield Road, Oxford, OX1 3SR, UK
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