1
|
Twining BS, Baines SB. Luxury iron uptake and storage in pennate diatoms from the equatorial Pacific Ocean. Metallomics 2022; 14:6596291. [PMID: 35641175 DOI: 10.1093/mtomcs/mfac035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 05/08/2022] [Indexed: 11/13/2022]
Abstract
Iron is a key micronutrient for ocean phytoplankton, and the availability of iron controls primary production and community composition in large regions of the ocean. Pennate diatoms, a phytoplankton group that responds to iron additions in low-iron areas, can have highly variable iron contents, and some groups such as Pseudo-nitzschia are known to use ferritin to store iron for later use. We quantified and mapped the intracellular accumulation of iron by a natural population of Pseudo-nitzschia from the Fe-limited equatorial Pacific Ocean. Forty-eight hours after iron addition, nearly half of accumulated iron was localized in storage bodies adjacent to chloroplasts believed to represent ferritin. Over the subsequent 48 h, stored iron was distributed to the rest of the cell through subsequent growth and division, partially supporting the iron contents of the daughter cells. This study provides a first quantitative view into the cellular trafficking of iron in a globally relevant phytoplankton group and demonstrates the unique capabilities of synchrotron-based element imaging approaches.
Collapse
Affiliation(s)
| | - Stephen B Baines
- Department of Ecology and Evolution, Stony Brook University, Stony Brook, NY
| |
Collapse
|
2
|
Girault M, Siano R, Labry C, Latimier M, Jauzein C, Beneyton T, Buisson L, Del Amo Y, Baret JC. Variable inter and intraspecies alkaline phosphatase activity within single cells of revived dinoflagellates. ISME JOURNAL 2021; 15:2057-2069. [PMID: 33568788 DOI: 10.1038/s41396-021-00904-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 01/04/2021] [Accepted: 01/20/2021] [Indexed: 01/21/2023]
Abstract
Adaptation of cell populations to environmental changes is mediated by phenotypic variability at the single-cell level. Enzyme activity is a key factor in cell phenotype and the expression of the alkaline phosphatase activity (APA) is a fundamental phytoplankton strategy for maintaining growth under phosphate-limited conditions. Our aim was to compare the APA among cells and species revived from sediments of the Bay of Brest (Brittany, France), corresponding to a pre-eutrophication period (1940's) and a beginning of a post-eutrophication period (1990's) during which phosphate concentrations have undergone substantial variations. Both toxic marine dinoflagellate Alexandrium minutum and the non-toxic dinoflagellate Scrippsiella acuminata were revived from ancient sediments. Using microfluidics, we measured the kinetics of APA at the single-cell level. Our results indicate that all S. acuminata strains had significantly higher APA than A. minutum strains. For both species, the APA in the 1990's decade was significantly lower than in the 1940's. For the first time, our results reveal both inter and intraspecific variabilities of dinoflagellate APA and suggest that, at a half-century timescale, two different species of dinoflagellate may have undergone similar adaptative evolution to face environmental changes and acquire ecological advantages.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Lionel Buisson
- Univ. Bordeaux, CNRS, CRPP, UMR5031, 33600, Pessac, France
| | - Yolanda Del Amo
- Université de Bordeaux, UMR CNRS 5805 EPOC, Station Marine d'Arcachon, 33120, Arcachon, France
| | - Jean-Christophe Baret
- Univ. Bordeaux, CNRS, CRPP, UMR5031, 33600, Pessac, France. .,Institut Universitaire de France, 75005, Paris, France.
| |
Collapse
|
3
|
Diaz JM, Steffen R, Sanders JG, Tang Y, Duhamel S. Preferential utilization of inorganic polyphosphate over other bioavailable phosphorus sources by the model diatoms Thalassiosira spp. Environ Microbiol 2019; 21:2415-2425. [PMID: 30972877 PMCID: PMC6849833 DOI: 10.1111/1462-2920.14630] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 04/02/2019] [Accepted: 04/08/2019] [Indexed: 11/28/2022]
Abstract
Polyphosphates and phosphomonoesters are dominant components of marine dissolved organic phosphorus (DOP). Collectively, DOP represents an important nutritional phosphorus (P) source for phytoplankton growth in the ocean, but the contribution of specific DOP sources to microbial community P demand is not fully understood. In a prior study, it was reported that inorganic polyphosphate was not bioavailable to the model diatoms Thalassiosira weissflogii and Thalassiosira pseudonana. However, in this study, we show that the previous finding was a misinterpretation based on a technical artefact of media preparation and that inorganic polyphosphate is actually widely bioavailable to Thalassiosira spp. In fact, orthophosphate, inorganic tripolyphosphate (3polyP), adenosine triphosphate (ATP) and adenosine monophosphate supported equivalent growth rates and final growth yields within each of four strains of Thalassiosira spp. However, enzyme activity assays revealed in all cultures that cell-associated hydrolysis rates of 3polyP were typically more than ~10-fold higher than degradation of ATP and the model phosphomonoester compound 4-methylumbelliferyl phosphate. These results build on prior work, which showed the preferential utilization of polyphosphates in the cell-free exudates of Thalassiosira spp., and suggest that inorganic polyphosphates may be a key bioavailable source of P for marine phytoplankton.
Collapse
Affiliation(s)
- Julia M Diaz
- Skidaway Institute of Oceanography, Department of Marine Sciences, University of Georgia, Savannah, GA, USA
| | - Rachel Steffen
- Skidaway Institute of Oceanography, Department of Marine Sciences, University of Georgia, Savannah, GA, USA
| | - James G Sanders
- Skidaway Institute of Oceanography, Department of Marine Sciences, University of Georgia, Savannah, GA, USA
| | - Yuanzhi Tang
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Solange Duhamel
- Lamont-Doherty Earth Observatory, Division of Biology and Paleo Environment, Palisades, NY, USA
| |
Collapse
|
4
|
Abstract
Diatoms are prominent eukaryotic phytoplankton despite being limited by the micronutrient iron in vast expanses of the ocean. As iron inputs are often sporadic, diatoms have evolved mechanisms such as the ability to store iron that enable them to bloom when iron is resupplied and then persist when low iron levels are reinstated. Two iron storage mechanisms have been previously described: the protein ferritin and vacuolar storage. To investigate the ecological role of these mechanisms among diatoms, iron addition and removal incubations were conducted using natural phytoplankton communities from varying iron environments. We show that among the predominant diatoms, Pseudo-nitzschia were favored by iron removal and displayed unique ferritin expression consistent with a long-term storage function. Meanwhile, Chaetoceros and Thalassiosira gene expression aligned with vacuolar storage mechanisms. Pseudo-nitzschia also showed exceptionally high iron storage under steady-state high and low iron conditions, as well as following iron resupply to iron-limited cells. We propose that bloom-forming diatoms use different iron storage mechanisms and that ferritin utilization may provide an advantage in areas of prolonged iron limitation with pulsed iron inputs. As iron distributions and availability change, this speculated ferritin-linked advantage may result in shifts in diatom community composition that can alter marine ecosystems and biogeochemical cycles.
Collapse
|
5
|
Lipidomics of Thalassiosira pseudonana under Phosphorus Stress Reveal Underlying Phospholipid Substitution Dynamics and Novel Diglycosylceramide Substitutes. Appl Environ Microbiol 2018; 84:AEM.02034-17. [PMID: 29305510 PMCID: PMC5835749 DOI: 10.1128/aem.02034-17] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 12/21/2017] [Indexed: 02/01/2023] Open
Abstract
Phytoplankton replace phosphorus-containing lipids (P-lipids) with non-P analogues, boosting growth in P-limited oceans. In the model diatom Thalassiosira pseudonana, the substitution dynamics of lipid headgroups are well described, but those of the individual lipids, differing in fatty acid composition, are unknown. Moreover, the behavior of lipids outside the common headgroup classes and the relationship between lipid substitution and cellular particulate organic P (POP) have yet to be reported. We investigated these through the mass spectrometric lipidomics of P-replete (P+) and P-depleted (P-) T. pseudonana cultures. Nonlipidic POP was depleted rapidly by the initiation of P stress, followed by the cessation of P-lipid biosynthesis and per-cell reductions in the P-lipid levels of successive generations. Minor P-lipid degradative breakdown was observed, releasing P for other processes, but most P-lipids remained intact. This may confer an advantage on efficient heterotrophic lipid consumers in P-limited oceans. Glycerophosphatidylcholine (PC), the predominant P-lipid, was similar in composition to its betaine substitute lipid. During substitution, PC was less abundant per cell and was more highly unsaturated in composition. This may reflect underlying biosynthetic processes or the regulation of membrane biophysical properties subject to lipid substitution. Finally, levels of several diglycosylceramide lipids increased as much as 10-fold under P stress. These represent novel substitute lipids and potential biomarkers for the study of P limitation in situ, contributing to growing evidence highlighting the importance of sphingolipids in phycology. These findings contribute much to our understanding of P-lipid substitution, a powerful and widespread adaptation to P limitation in the oligotrophic ocean.IMPORTANCE Unicellular organisms replace phosphorus (P)-containing membrane lipids with non-P substitutes when P is scarce, allowing greater growth of populations. Previous research with the model diatom species Thalassiosira pseudonana grouped lipids by polar headgroups in their chemical structures. The significance of the research reported here is threefold. (i) We described the individual lipids within the headgroups during P-lipid substitution, revealing the relationships between lipid headgroups and hinting at the underlying biochemical processes. (ii) We measured total cellular P, placing P-lipid substitution in the context of the broader response to P stress and yielding insight into the implications of substitution in the marine environment. (iii) We identified lipids previously unknown in this system, revealing a new type of non-P substitute lipid, which is potentially useful as a biomarker for the investigation of P limitation in the ocean.
Collapse
|
6
|
Wang D, Xia W, Kumar KS, Gao K. Increasing copper alters cellular elemental composition (Mo and P) of marine diatom. Ecol Evol 2017; 7:3362-3371. [PMID: 28515872 PMCID: PMC5433991 DOI: 10.1002/ece3.2890] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 01/21/2017] [Accepted: 02/10/2017] [Indexed: 11/15/2022] Open
Abstract
The elemental composition (surface adsorbed and internalized fraction of Cu, Mo and P) in marine phytoplankton was first examined in cultures of the diatom Phaeodactylum tricornutum which were exposed to various levels of Cu concentrations ranging from 0.25 to 16 μmol/L with equivalent free [Cu2+] concentrations of 0.4-26 nmol/L. We observed an acceleration of algal growth rates (20-40%) with increasing ambient Cu levels, as well as slightly increased levels of internalized Cu in cells (2-13 × 10-18 mol/cell) although cellular Cu mostly accumulated onto the cell surface (>50% of the total: intracellular + surface adsorbed). In particular, we documented for the first time that the elemental composition (Mo and P) in algal cells varies dynamically in response to increased Cu levels: (1) Cellular P, predominantly in the intracellular compartment (>95%), shows with a net consumption as indicated by a gradual decrease with increasing [Cu2+] (120→50 × 10-15 mol P/cell) probably due to the fact that P, a backbone bioelement, is largely required in forming biological compartments such as cell membranes; and (2) cellular Mo, predominantly encountered in the intracellular compartment, showed up to tenfold increase in concentration in the cultures exposed to Cu, with a peak accumulation of 1.1 × 10-18 mol Mo/cell occurring in the culture exposed to [Cu2+] at 3.7 nmol/L. Such a net cellular Mo accumulation suggests that Mo might be specifically required in biological processes, probably playing a counteracting role against Cu.
Collapse
Affiliation(s)
- Deli Wang
- State Key Laboratory of Marine Environmental ScienceXiamen UniversityXiamenChina
| | - Weiwei Xia
- State Key Laboratory of Marine Environmental ScienceXiamen UniversityXiamenChina
| | - K. Suresh Kumar
- Department of BotanyUniversity of AllahabadAllahabad 211002India
| | - Kunshan Gao
- State Key Laboratory of Marine Environmental ScienceXiamen UniversityXiamenChina
| |
Collapse
|
7
|
Segura-Noguera M, Blasco D, Fortuño JM. Taxonomic and Environmental Variability in the Elemental Composition and Stoichiometry of Individual Dinoflagellate and Diatom Cells from the NW Mediterranean Sea. PLoS One 2016; 11:e0154050. [PMID: 27111067 PMCID: PMC4844132 DOI: 10.1371/journal.pone.0154050] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 04/07/2016] [Indexed: 11/19/2022] Open
Abstract
Here we present, for the first time, the elemental concentration, including C, N and O, of single phytoplankton cells collected from the sea. Plankton elemental concentration and stoichiometry are key variables in phytoplankton ecophysiology and ocean biogeochemistry, and are used to link cells and ecosystems. However, most field studies rely on bulk techniques that overestimate carbon and nitrogen because the samples include organic matter other than plankton organisms. Here we used X-ray microanalysis (XRMA), a technique that, unlike bulk analyses, gives simultaneous quotas of C, N, O, Mg, Si, P, and S, in single-cell organisms that can be collected directly from the sea. We analysed the elemental composition of dinoflagellates and diatoms (largely Chaetoceros spp.) collected from different sites of the Catalan coast (NW Mediterranean Sea). As expected, a lower C content is found in our cells compared to historical values of cultured cells. Our results indicate that, except for Si and O in diatoms, the mass of all elements is not a constant fraction of cell volume but rather decreases with increasing cell volume. Also, diatoms are significantly less dense in all the measured elements, except Si, compared to dinoflagellates. The N:P ratio of both groups is higher than the Redfield ratio, as it is the N:P nutrient ratio in deep NW Mediterranean Sea waters (N:P = 20-23). The results suggest that the P requirement is highest for bacterioplankton, followed by dinoflagellates, and lowest for diatoms, giving them a clear ecological advantage in P-limited environments like the Mediterranean Sea. Finally, the P concentration of cells of the same genera but growing under different nutrient conditions was the same, suggesting that the P quota of these cells is at a critical level. Our results indicate that XRMA is an accurate technique to determine single cell elemental quotas and derived conversion factors used to understand and model ocean biogeochemical cycles.
Collapse
Affiliation(s)
- Mariona Segura-Noguera
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar (CSIC), Barcelona, Catalonia
| | - Dolors Blasco
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar (CSIC), Barcelona, Catalonia
| | - José-Manuel Fortuño
- Department of Marine Biology and Oceanography, Institut de Ciències del Mar (CSIC), Barcelona, Catalonia
| |
Collapse
|
8
|
Baines SB, Chen X, Vogt S, Fisher NS, Twining BS, Landry MR. Microplankton trace element contents: implications for mineral limitation of mesozooplankton in an HNLC area. JOURNAL OF PLANKTON RESEARCH 2016; 38:256-270. [PMID: 27275029 PMCID: PMC4889991 DOI: 10.1093/plankt/fbv109] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Accepted: 11/19/2015] [Indexed: 05/25/2023]
Abstract
Mesozooplankton production in high-nutrient low-chlorophyll regions of the ocean may be reduced if the trace element concentrations in their food are insufficient to meet growth and metabolic demands. We used elemental microanalysis (SXRF) of single-celled plankton to determine their trace metal contents during a series of semi-Lagrangian drift studies in an HNLC upwelling region, the Costa Rica Dome (CRD). Cells from the surface mixed layer had lower Fe:S but higher Zn:S and Ni:S than those from the subsurface chlorophyll maximum at 22-30 m. Diatom Fe:S values were typically 3-fold higher than those in flagellated cells. The ratios of Zn:C in flagellates and diatoms were generally similar to each other, and to co-occurring mesozooplankton. Estimated Fe:C ratios in flagellates were lower than those in co-occurring mesozooplankton, sometimes by more than 3-fold. In contrast, Fe:C in diatoms was typically similar to that in zooplankton. RNA:DNA ratios in the CRD were low compared with other regions, and were related to total autotrophic biomass and weakly to the discrepancy between Zn:C in flagellated cells and mesozooplankton tissues. Mesozooplankton may have been affected by the trace element content of their food, even though trace metal limitation of phytoplankton was modest at best.
Collapse
Affiliation(s)
- Stephen B. Baines
- Department of Ecology and Evolution, Stony Brook University, Stony Brook, NY 11789-5245, USA
| | - Xi Chen
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11789-5000, USA
| | - Stefan Vogt
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Nicholas S. Fisher
- School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11789-5000, USA
| | | | - Michael R. Landry
- Scripps Institution of Oceanography, University of California at San Diego, 9500 Gilman Dr, La Jolla, CA 92093-0227, USA
| |
Collapse
|
9
|
Rashkow JT, Patel SC, Tappero R, Sitharaman B. Quantification of single-cell nanoparticle concentrations and the distribution of these concentrations in cell population. J R Soc Interface 2014; 11:20131152. [PMID: 24554576 PMCID: PMC3973359 DOI: 10.1098/rsif.2013.1152] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 01/27/2014] [Indexed: 11/12/2022] Open
Abstract
Quantification of nanoparticle uptake into cells is necessary for numerous applications in cellular imaging and therapy. Herein, synchrotron X-ray fluorescence (SXRF) microscopy, a promising tool to quantify elements in plant and animal cells, was employed to quantify and characterize the distribution of titanium dioxide (TiO2) nanosphere uptake in a population of single cells. These results were compared with average nanoparticle concentrations per cell obtained by widely used inductively coupled plasma mass spectrometry (ICP-MS). The results show that nanoparticle concentrations per cell quantified by SXRF were of one to two orders of magnitude greater compared with ICP-MS. The SXRF results also indicate a Gaussian distribution of the nanoparticle concentration per cell. The results suggest that issues relevant to the field of single-cell analysis, the limitation of methods to determine physical parameters from large population averages leading to potentially misleading information and the lack of any information about the cellular heterogeneity are equally relevant for quantification of nanoparticles in cell populations.
Collapse
Affiliation(s)
- Jason T. Rashkow
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794-5281, USA
| | - Sunny C. Patel
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794-5281, USA
| | - Ryan Tappero
- Department of Photon Sciences, National Synchrotron Light Source, Brookhaven National Lab, Upton, NY 11973-5000, USA
| | - Balaji Sitharaman
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794-5281, USA
| |
Collapse
|
10
|
Nuester J, Newville M, Twining BS. Distributions of iron, phosphorus and sulfur along trichomes of the cyanobacteria Trichodesmium. Metallomics 2014; 6:1141-9. [DOI: 10.1039/c4mt00042k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Changes in the elemental composition within trichomes of the nonheterocystous cyanobacteriaTrichodesmiumare potentially related to N2-fixation.
Collapse
Affiliation(s)
| | - Matthew Newville
- Center for Advanced Radiation Sources
- The University of Chicago
- Argonne, USA
| | | |
Collapse
|
11
|
Use of agent-based modeling to explore the mechanisms of intracellular phosphorus heterogeneity in cultured phytoplankton. Appl Environ Microbiol 2013; 79:4359-68. [PMID: 23666327 DOI: 10.1128/aem.00487-13] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
There can be significant intraspecific individual-level heterogeneity in the intracellular P of phytoplankton, which can affect the population-level growth rate. Several mechanisms can create this heterogeneity, including phenotypic variability in various physiological functions (e.g., nutrient uptake rate). Here, we use modeling to explore the contribution of various mechanisms to the heterogeneity in phytoplankton grown in a laboratory culture. An agent-based model simulates individual cells and their intracellular P. Heterogeneity is introduced by randomizing parameters (e.g., maximum uptake rate) of daughter cells at division. The model was calibrated to observations of the P quota of individual cells of the centric diatom Thalassiosira pseudonana, which were obtained using synchrotron X-ray fluorescence (SXRF). A number of simulations, with individual mechanisms of heterogeneity turned off, then were performed. Comparison of the coefficient of variation (CV) of these and the baseline simulation (i.e., all mechanisms turned on) provides an estimate of the relative contribution of these mechanisms. The results show that the mechanism with the largest contribution to variability is the parameter characterizing the maximum intracellular P, which, when removed, results in a CV of 0.21 compared to a CV of 0.37 with all mechanisms turned on. This suggests that nutrient/element storage capabilities/mechanisms are important determinants of intrapopulation heterogeneity.
Collapse
|
12
|
Abstract
Trace metals are required for numerous processes in phytoplankton and can influence the growth and structure of natural phytoplankton communities. The metal contents of phytoplankton reflect biochemical demands as well as environmental availability and influence the distribution of metals in the ocean. Metal quotas of natural populations can be assessed from analyses of individual cells or bulk particle assemblages or inferred from ratios of dissolved metals and macronutrients in the water column. Here, we review the available data from these approaches for temperate, equatorial, and Antarctic waters in the Pacific and Atlantic Oceans. The data show a generalized metal abundance ranking of Fe≈Zn>Mn≈Ni≈Cu≫Co≈Cd; however, there are notable differences between taxa and regions that inform our understanding of ocean metal biogeochemistry. Differences in the quotas estimated by the various techniques also provide information on metal behavior. Therefore, valuable information is lost when a single metal stoichiometry is assumed for all phytoplankton.
Collapse
|
13
|
Chen H, Rogalski MM, Anker JN. Advances in functional X-ray imaging techniques and contrast agents. Phys Chem Chem Phys 2012; 14:13469-86. [PMID: 22962667 PMCID: PMC3569739 DOI: 10.1039/c2cp41858d] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
X-rays have been used for non-invasive high-resolution imaging of thick biological specimens since their discovery in 1895. They are widely used for structural imaging of bone, metal implants, and cavities in soft tissue. Recently, a number of new contrast methodologies have emerged which are expanding X-ray's biomedical applications to functional as well as structural imaging. These techniques are promising to dramatically improve our ability to study in situ biochemistry and disease pathology. In this review, we discuss how X-ray absorption, X-ray fluorescence, and X-ray excited optical luminescence can be used for physiological, elemental, and molecular imaging of vasculature, tumors, pharmaceutical distribution, and the surface of implants. Imaging of endogenous elements, exogenous labels, and analytes detected with optical indicators will be discussed.
Collapse
Affiliation(s)
- Hongyu Chen
- Department of Chemistry, Center for Optical Materials Science and Engineering Technology (COMSET), Clemson University, Clemson, SC 29634, USA
| | | | | |
Collapse
|
14
|
Nuester J, Vogt S, Twining BS. LOCALIZATION OF IRON WITHIN CENTRIC DIATOMS OF THE GENUS THALASSIOSIRA(1). JOURNAL OF PHYCOLOGY 2012; 48:626-634. [PMID: 27011078 DOI: 10.1111/j.1529-8817.2012.01165.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The cellular iron (Fe) quota of centric diatoms has been shown to vary in response to the ambient dissolved Fe concentration; however, it is not known how centric diatoms store excess intracellular Fe. Here, we use synchrotron X-ray fluorescence (SXRF) element mapping to identify Fe storage features in cells of Thalassiosira pseudonana Hasle et Heimdal and Thalassiosira weissflogii G. A. Fryxell et Hasle grown at low and high Fe concentrations. Localized intracellular Fe storage features, defined as anomalously high Fe concentrations in regions of relatively low phosphorus (P), sulfur (S), silicon (Si), and zinc (Zn), were twice as common in T. weissflogii cells grown at high Fe compared to low-Fe cells. Cellular Fe quotas of this strain increased 2.9-fold, the spatial extent of the features increased 4.6-fold, and the Fe content of the features increased 14-fold under high-Fe conditions, consistent with a vacuole storage mechanism. The element stoichiometry of the Fe features is consistent with polyphosphate-bound Fe as a potential vacuolar Fe storage pool. Iron quotas increased 2.5-fold in T. pseudonana grown at high Fe, but storage features contained only 2-fold more Fe and did not increase in size compared to low-Fe cells. The differences in Fe storage observed between T. pseudonana and T. weissflogii may have been due to differences in the growth states of the cultures.
Collapse
Affiliation(s)
- Jochen Nuester
- Bigelow Laboratory for Ocean Sciences, East Boothbay, Maine 04544, USAX-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USABigelow Laboratory for Ocean Sciences, East Boothbay, Maine 04544, USA
| | - Stefan Vogt
- Bigelow Laboratory for Ocean Sciences, East Boothbay, Maine 04544, USAX-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USABigelow Laboratory for Ocean Sciences, East Boothbay, Maine 04544, USA
| | - Benjamin S Twining
- Bigelow Laboratory for Ocean Sciences, East Boothbay, Maine 04544, USAX-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USABigelow Laboratory for Ocean Sciences, East Boothbay, Maine 04544, USA
| |
Collapse
|
15
|
Nuester J, Vogt S, Newville M, Kustka AB, Twining BS. The unique biogeochemical signature of the marine diazotroph trichodesmium. Front Microbiol 2012; 3:150. [PMID: 22557997 PMCID: PMC3337509 DOI: 10.3389/fmicb.2012.00150] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 03/30/2012] [Indexed: 11/13/2022] Open
Abstract
The elemental composition of phytoplankton can depart from canonical Redfield values under conditions of nutrient limitation or production (e.g., N fixation). Similarly, the trace metal metallome of phytoplankton may be expected to vary as a function of both ambient nutrient concentrations and the biochemical processes of the cell. Diazotrophs such as the colonial cyanobacteria Trichodesmium are likely to have unique metal signatures due to their cell physiology. We present metal (Fe, V, Zn, Ni, Mo, Mn, Cu, Cd) quotas for Trichodesmium collected from the Sargasso Sea which highlight the unique metallome of this organism. The element concentrations of bulk colonies and trichomes sections were analyzed by ICP-MS and synchrotron x-ray fluorescence, respectively. The cells were characterized by low P contents but enrichment in V, Fe, Mo, Ni, and Zn in comparison to other phytoplankton. Vanadium was the most abundant metal in Trichodesmium, and the V quota was up to fourfold higher than the corresponding Fe quota. The stoichiometry of 600C:101N:1P (mol mol(-1)) reflects P-limiting conditions. Iron and V were enriched in contiguous cells of 10 and 50% of Trichodesmium trichomes, respectively. The distribution of Ni differed from other elements, with the highest concentration in the transverse walls between attached cells. We hypothesize that the enrichments of V, Fe, Mo, and Ni are linked to the biochemical requirements for N fixation either directly through enrichment in the N-fixing enzyme nitrogenase or indirectly by the expression of enzymes responsible for the removal of reactive oxygen species. Unintentional uptake of V via P pathways may also be occurring. Overall, the cellular content of trace metals and macronutrients differs significantly from the (extended) Redfield ratio. The Trichodesmium metallome is an example of how physiology and environmental conditions can cause significant deviations from the idealized stoichiometry.
Collapse
Affiliation(s)
- Jochen Nuester
- Bigelow Laboratory for Ocean SciencesEast Boothbay, ME, USA
| | - Stefan Vogt
- X-ray Science Division, Advanced Photon Source, Argonne National LaboratoryArgonne, IL, USA
| | - Matthew Newville
- Center for Advanced Radiation Sources, The University of ChicagoArgonne, IL, USA
| | - Adam B. Kustka
- Department of Earth and Environmental Sciences, Rutgers UniversityNewark, NJ, USA
| | | |
Collapse
|
16
|
Cardoso SC, Stelling MP, Paulsen BS, Rehen SK. Synchrotron radiation X-ray microfluorescence reveals polarized distribution of atomic elements during differentiation of pluripotent stem cells. PLoS One 2011; 6:e29244. [PMID: 22195032 PMCID: PMC3241705 DOI: 10.1371/journal.pone.0029244] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2011] [Accepted: 11/23/2011] [Indexed: 12/29/2022] Open
Abstract
The mechanisms underlying pluripotency and differentiation in embryonic and reprogrammed stem cells are unclear. In this work, we characterized the pluripotent state towards neural differentiated state through analysis of trace elements distribution using the Synchrotron Radiation X-ray Fluorescence Spectroscopy. Naive and neural-stimulated embryoid bodies (EB) derived from embryonic and induced pluripotent stem (ES and iPS) cells were irradiated with a spatial resolution of 20 µm to make elemental maps and qualitative chemical analyses. Results show that these embryo-like aggregates exhibit self-organization at the atomic level. Metallic elements content rises and consistent elemental polarization pattern of P and S in both mouse and human pluripotent stem cells were observed, indicating that neural differentiation and elemental polarization are strongly correlated.
Collapse
Affiliation(s)
- Simone C. Cardoso
- Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Mariana P. Stelling
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Bruna S. Paulsen
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Stevens K. Rehen
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail:
| |
Collapse
|
17
|
Affiliation(s)
- Yuqing Lin
- Department of Chemistry, University of Gothenburg, S-41296, Gothenburg, Sweden
| | | | | | | |
Collapse
|
18
|
Qin Z, Toursarkissian B, Lai B. Synchrotron radiation X-ray fluorescence microscopy reveals a spatial association of copper on elastic laminae in rat aortic media. Metallomics 2011; 3:823-8. [PMID: 21589993 DOI: 10.1039/c1mt00033k] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Copper, an essential trace metal in humans, plays an important role in elastic formation. However, little is known about the spatial association between copper, elastin, and elastin producing cells. The aorta is the largest artery; the aortic media is primarily composed of the elastic lamellae and vascular smooth muscle cells, which makes it a good model to address this issue. Synchrotron radiation X-ray fluorescence microscopy (SRXRF) is a new generation technique to investigate the spatial topography of trace metals in biological samples. Recently, we utilized this technique to determine the topography of copper as well as other trace elements in aortic media of Sprague Dawley rats. A standard rat diet was used to feed Sprague Dawley rats, which contains the normal dietary requirements of copper and zinc. Paraffin embedded segments (4 μm of thickness) of thoracic aorta were analyzed using a 10 keV incident monochromatic X-ray beam focusing on a spot size of 0.3 μm × 0.2 μm (horizontal × vertical). The X-ray spectrum was measured using an energy-dispersive silicon drift detector for elemental topography. Our results showed that phosphorus, sulfur, and zinc are predominately distributed in the vascular smooth muscle cells, whereas copper is dramatically accumulated in elastic laminae, indicating a preferential spatial association of copper on elastic laminae in aortic media. This finding sheds new light on the role of copper in elastic formation. Our studies also demonstrate that SRXRF allows for the visualization of trace elements in tissues and cells of rodent aorta with high spatial resolution and provides an opportunity to study the role of trace elements in vasculature.
Collapse
Affiliation(s)
- Zhenyu Qin
- Division of Vascular Surgery, Department of Surgery, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, Texas 78229, USA.
| | | | | |
Collapse
|