Stable Carbon Isotopic Fractionations Associated with Inorganic Carbon Fixation by Anaerobic Ammonium-Oxidizing Bacteria

ABSTRACT Isotopic analyses of Candidatus “Brocadia anammoxidans,” a chemolithoautotrophic bacterium that anaerobically oxidizes ammonium (anammox), show that it strongly fractionates against 13C; i.e., lipids are depleted by up to 47‰ versus CO2. Similar results were obtained for the anammox bacterium Candidatus “Scalindua sorokinii,” which thrives in the anoxic water column of the Black Sea, suggesting that different anammox bacteria use identical carbon fixation pathways, which may be either the Calvin cycle or the acetyl coenzyme A pathway.

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Origin of atmospheric polycyclic aromatic hydrocarbons (PAHs) in Chinese cities solved by compound-specific stable carbon isotopic analyses

Organic Geochemistry ◽

10.1016/s0146-6380(02)00180-8 ◽

2002 ◽

Vol 33 (12) ◽

pp. 1737-1745 ◽

Cited By ~ 51

Author(s):

Tomoaki Okuda ◽

Hidetoshi Kumata ◽

Hiroshi Naraoka ◽

Hideshige Takada

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Aromatic Hydrocarbons ◽

Stable Carbon ◽

Chinese Cities ◽

Carbon Isotopic ◽

Isotopic Analyses ◽

Polycyclic Aromatic

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Radiocarbon dating and stable carbon isotopic analyses of Neolithic and Bronze Age staple crops in the lower Yellow River area and their paleodietary implications

Geoarchaeology ◽

10.1002/gea.21659 ◽

2017 ◽

Vol 33 (3) ◽

pp. 307-313 ◽

Cited By ~ 6

Author(s):

Xue-Xiang Chen ◽

Shi-Yong Yu ◽

Anne P. Underhill ◽

Hui Fang

Keyword(s):

Bronze Age ◽

Radiocarbon Dating ◽

Yellow River ◽

Stable Carbon ◽

Lower Yellow River ◽

The Lower Yellow River ◽

Carbon Isotopic ◽

Isotopic Analyses ◽

Staple Crops

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Factors influencing the stable carbon isotopic composition of suspended and sinking organic matter in the coastal Antarctic sea ice environment

Biogeosciences Discussions ◽

10.5194/bgd-8-11041-2011 ◽

2011 ◽

Vol 8 (6) ◽

pp. 11041-11088 ◽

Cited By ~ 1

Author(s):

S. F. Henley ◽

A. L. Annett ◽

R. S. Ganeshram ◽

D. S. Carson ◽

K. Weston ◽

...

Keyword(s):

Sea Ice ◽

Surface Waters ◽

Carbon Fixation ◽

Carbon Isotopic Composition ◽

Austral Summer ◽

Sediment Traps ◽

Diatom Species ◽

Stable Carbon ◽

Sedimentary Record ◽

Carbon Isotopic

Abstract. A high resolution time-series analysis of stable carbon isotopic signatures in particulate organic carbon (δ13CPOC) and associated biogeochemical parameters in sea ice and surface waters provides an insight into the factors affecting δ13CPOC in the coastal western Antarctic Peninsula (WAP) sea ice environment. The study covers two austral summer seasons in Ryder Bay, northern Marguerite Bay between 2004 and 2006. A shift in diatom species composition during the 2005/2006 summer bloom to near-complete biomass dominance of Proboscia inermis is strongly correlated with a large ~10‰ negative isotopic shift in δ13CPOC that cannot be explained by a concurrent change in concentration or isotopic signature of CO2. We hypothesise that the δ13CPOC shift may be driven by the contrasting biochemical mechanisms and utilisation of carbon-concentrating mechanisms in different diatom species. These short-lived yet pronounced negative δ13CPOC excursions drive a 4‰ decrease in the seasonal average δ13CPOC signal, which is transferred to sediment traps and core-top sediments and consequently has the potential for preservation in the sedimentary record. This 4‰ difference between seasons of contrasting sea ice conditions and upper water column stratification matches the full amplitude of glacial-interglacial Southern Ocean δ13CPOC variability and, as such, we invoke phytoplankton species changes as a potentially important factor influencing sedimentary δ13CPOC. We also find significantly higher δ13CPOC in sea ice than surface waters, consistent with autotrophic carbon fixation in a semi-closed environment and possible contributions from post-production degradation, biological utilisation of HCO3- and production of exopolymeric substances (EPS). This study demonstrates the importance of surface water diatom speciation effects and isotopically heavy sea ice-derived material for δ13CPOC in Antarctic coastal environments and underlying sediments, with consequences for the utility of diatom-based δ13CPOC in the sedimentary record.

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Stable carbon isotope analysis of faecal and blood samples of sheep in relation to the diet

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200013181 ◽

2003 ◽

Vol 2003 ◽

pp. 159-159

Author(s):

A. Balcaen ◽

E. Claeys ◽

V. Fievez ◽

P. Boeckx ◽

O. van Cleemput ◽

...

Keyword(s):

Isotopic Composition ◽

Carbon Isotope ◽

Carbon Fixation ◽

Isotope Composition ◽

Stable Carbon Isotope ◽

Isotope Analysis ◽

Calvin Cycle ◽

Isotopic Fractionation ◽

Woody Species ◽

Stable Carbon

Stable isotopes have been extraordinarily helpful in understanding animal migration, diet, food webs and nutrient flow (Hilderbrand et al., 1996), based on the property that C3 and C4 plants possess distinctly different 13C/12C ratios (δ13C value) due to isotopic fractionation during photosynthetic carbon fixation (Smith & Epstein, 1971). Most woody species and temperate graminoids assimilate carbon via the Calvin cycle (C3), which discriminates stronger against the heavier isotope (13C) than Hatch-Slack (C4) species (tropical and subtropical graminoids and some shrubs). C3 and C4 plant species have mean δ13C values of -27 ‰ and -13 ‰ respectively (O’Leary, 1981). DeNiro & Epstein (1978) were one of the first to show that the isotopic composition of the whole animal body is similar to that of its diet. Other authors have also found relationships between the isotopic composition of animal tissues and the diet (González-Martin et al., 1999; Jones et al., 1979). The aim of this study was to investigate stable carbon isotope composition in sheep fed diets consisting of either C3 or C3+C4 plants.

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Photosynthesis in the Aquatic Macrophyte Egeria densa. II. Effects of Inorganic Carbon Conditions on 14C Fixation

Functional Plant Biology ◽

10.1071/pp9790001 ◽

1979 ◽

Vol 6 (1) ◽

pp. 1 ◽

Cited By ~ 19

Author(s):

JA Browse ◽

JMA Brown ◽

FI Dromgoole

Keyword(s):

Inorganic Carbon ◽

Carbon Fixation ◽

Aquatic Macrophyte ◽

Calvin Cycle ◽

Total Carbon ◽

Absolute Amount ◽

Ambient Conditions ◽

Fixation Rate ◽

Rate Of Photosynthesis ◽

Time Courses

In short-term labelling experiments, tripling the concentration of total inorganic carbon (TIC) did not significantly increase the high rates of 14C fixation reported in an earlier paper [19.0 μmol C (g dry wt)-1 min-1 at pH 6.8, [TIC] = 1 mM]. However, either decreasing [TIC] or increasing the pH caused the fixation rate to fall markedly. Thus at pH 6.8, [TIC] = 38 μM and pH 10.2, [TIC] = 1.0 mM, photosynthesis was 2.3 and 1.3 μmol g-1 min-1, respectively. Time courses of the distribution of photosynthetic intermediates indicated that the Calvin cycle remained the predominant pathway of carbon fixation, irrespective of the ambient conditions of TIC and pH. When the rate of photosynthesis was reduced by decreasing [TIC] or increasing pH, the proportion (but not the absolute amount) of label found in malate increased. At pH 6.8, [TIC] = 2.9 mM, μ-carboxylation accounted for only 2.7% of the total carbon fixed, compared with 9% at air levels of CO2 (pH 4.5, [TIC] = 13 μM). Egeria does not appear to exhibit C4 photosynthesis under any of the conditions studied, but malate may be a significant product of photosynthesis whenever the fixation rate is reduced by carbon availability.

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