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Kalaitzis P, Sofikitis D, Kosmidis C. The role of predissociation states in the UV photooxidation of acetylene. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2022.114373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Akob DM, Sutton JM, Bushman TJ, Baesman SM, Klein E, Shrestha Y, Andrews R, Fierst JL, Kolton M, Gushgari-doyle S, Oremland RS, Freeman JL. Acetylenotrophic and Diazotrophic Bradyrhizobium sp. Strain I71 from TCE-Contaminated Soils. Appl Environ Microbiol 2022. [PMID: 36286524 PMCID: PMC9680620 DOI: 10.1128/aem.01219-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The isolation of
Bradyrhizobium
strain I71 expands the distribution of acetylene-consuming microbes to include a group of economically important microorganisms. Members of
Bradyrhizobium
are well studied for their abilities to improve plant health and increase crop yields by providing bioavailable nitrogen.
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Mirsaleh-Kohan N, Esmaili S, Bass AD, Huels MA, Sanche L. Chemical transformation of molecular ices containing N 2O and C 2D 2 by low energy electrons: New chemical species of astronomical interest. J Chem Phys 2021; 154:224706. [PMID: 34241211 DOI: 10.1063/5.0040884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have employed electron stimulated desorption (ESD) and x-ray photoelectron spectroscopy (XPS) to study the chemical species generated from multilayer films of N2O, C2D2, and mixtures thereof (i.e., N2O/C2D2) by the impact of low energy electrons with energies between 30 and 70 eV. Our ESD results for pure films of N2O show the production of numerous fragment cations and anions, and of larger molecular ions, of sufficient kinetic energy to escape into vacuum, which are likely formed by ion-molecule scattering in the film. Ion-molecule scattering is also responsible for the production of cations from C2D2 films that contain as many as six or seven carbon atoms. Many of the same anions and cations desorb from N2O/C2D2 mixtures, as well as new species, which is the result of ion-molecule scattering in the film. Anion desorption signals further indicate the formation of C-N containing species within the irradiated films. XPS spectra of N1s, C1s, and O1s lines reveal the fragmentation of N-O bonds and gradual formation of molecules containing species containing O-C=O, C=O, and C-O functional groups. A comparison between ESD and XPS findings suggests that species observed in the ESD channel are primarily products of reactions taking place at the film-vacuum interface, while those observed in the XPS derive from reactions occurring within the solid.
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Affiliation(s)
- Nasrin Mirsaleh-Kohan
- Département de Médecine Nucléaire et Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H 5N4, Canada
| | - Sasan Esmaili
- Département de Médecine Nucléaire et Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H 5N4, Canada
| | - Andrew D Bass
- Département de Médecine Nucléaire et Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H 5N4, Canada
| | - Michael A Huels
- Département de Médecine Nucléaire et Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H 5N4, Canada
| | - Leon Sanche
- Département de Médecine Nucléaire et Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1H 5N4, Canada
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Zou M, Yang Z, Sun L, Ming X. Acetylene sensing system based on wavelength modulation spectroscopy using a triple-row circular multi-pass cell. Opt Express 2020; 28:11573-11582. [PMID: 32403665 DOI: 10.1364/oe.388343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 03/30/2020] [Indexed: 06/11/2023]
Abstract
A sensitive acetylene (C2H2) sensing system based on a novel triple-row circular multi-pass cell (CMPC) was demonstrated. This CMPC has an effective optical length of 21.9 m within an extremely small volume of 100.1 mL. We utilized wavelength modulation spectroscopy (WMS) for absorption spectroscopy detection of C2H2. The distance between the two minima of the second harmonic was used to normalize the maximum value of it, which makes the time to obtain stable output for continuous detection shorten dramatically. A fiber-coupled distributed feedback (DFB) diode laser emitting at 1.5316 µm was employed as a light source. An Allan deviation analysis yielded a detection sensitivity of 76.75 ppb with a normalized noise equivalent absorption coefficient of 8.8 × 10-10 cm-1 Hz-1/2 during an average time of 340 s. With a fast stable time, reduced size and high detection sensitivity, the proposed sensing system is suitable for trace gas sensing in a weight-limited unmanned aerial vehicle (UAV) and an exhalation diagnosis for smoking test.
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Chen X, Millet DB, Singh HB, Wisthaler A, Apel EC, Atlas EL, Blake DR, Bourgeois I, Brown SS, Crounse JD, de Gouw JA, Flocke FM, Fried A, Heikes BG, Hornbrook RS, Mikoviny T, Min KE, Müller M, Neuman JA, O'Sullivan DW, Peischl J, Pfister GG, Richter D, Roberts JM, Ryerson TB, Shertz SR, Thompson CR, Treadaway V, Veres PR, Walega J, Warneke C, Washenfelder RA, Weibring P, Yuan B. On the sources and sinks of atmospheric VOCs: an integrated analysis of recent aircraft campaigns over North America. Atmos Chem Phys 2019; 19:9097-9123. [PMID: 33688334 PMCID: PMC7939023 DOI: 10.5194/acp-19-9097-2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
We apply a high-resolution chemical transport model (GEOS-Chem CTM) with updated treatment of volatile organic compounds (VOCs) and a comprehensive suite of airborne datasets over North America to (i) characterize the VOC budget and (ii) test the ability of current models to capture the distribution and reactivity of atmospheric VOCs over this region. Biogenic emissions dominate the North American VOC budget in the model, accounting for 70 % and 95 % of annually emitted VOC carbon and reactivity, respectively. Based on current inventories anthropogenic emissions have declined to the point where biogenic emissions are the dominant summertime source of VOC reactivity even in most major North American cities. Methane oxidation is a 2x larger source of nonmethane VOCs (via production of formaldehyde and methyl hydroperoxide) over North America in the model than are anthropogenic emissions. However, anthropogenic VOCs account for over half of the ambient VOC loading over the majority of the region owing to their longer aggregate lifetime. Fires can be a significant VOC source episodically but are small on average. In the planetary boundary layer (PBL), the model exhibits skill in capturing observed variability in total VOC abundance (R 2 = 0:36) and reactivity (R 2 = 0:54). The same is not true in the free troposphere (FT), where skill is low and there is a persistent low model bias (~ 60 %), with most (27 of 34) model VOCs underestimated by more than a factor of 2. A comparison of PBL: FT concentration ratios over the southeastern US points to a misrepresentation of PBL ventilation as a contributor to these model FT biases. We also find that a relatively small number of VOCs (acetone, methanol, ethane, acetaldehyde, formaldehyde, isoprene C oxidation products, methyl hydroperoxide) drive a large fraction of total ambient VOC reactivity and associated model biases; research to improve understanding of their budgets is thus warranted. A source tracer analysis suggests a current overestimate of biogenic sources for hydroxyacetone, methyl ethyl ketone and glyoxal, an underestimate of biogenic formic acid sources, and an underestimate of peroxyacetic acid production across biogenic and anthropogenic precursors. Future work to improve model representations of vertical transport and to address the VOC biases discussed are needed to advance predictions of ozone and SOA formation.
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Affiliation(s)
- Xin Chen
- Department of Soil, Water, and Climate, University of Minnesota, Minneapolis-Saint Paul, MN, USA
| | - Dylan B. Millet
- Department of Soil, Water, and Climate, University of Minnesota, Minneapolis-Saint Paul, MN, USA
| | | | - Armin Wisthaler
- Institute for Ion Physics and Applied Physics, University of Innsbruck, 6020 Innsbruck, Austria
- Department of Chemistry, University of Oslo, Oslo, Norway
| | - Eric C. Apel
- Atmospheric Chemistry Observations & Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - Elliot L. Atlas
- Department of Atmospheric Sciences, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA
| | - Donald R. Blake
- Department of Chemistry, University of California, Irvine, Irvine, CA, USA
| | - Ilann Bourgeois
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - Steven S. Brown
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - John D. Crounse
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
| | - Joost A. de Gouw
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - Frank M. Flocke
- Atmospheric Chemistry Observations & Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - Alan Fried
- Institute of Arctic & Alpine Research, University of Colorado, Boulder, CO, USA
| | - Brian G. Heikes
- Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, USA
| | - Rebecca S. Hornbrook
- Atmospheric Chemistry Observations & Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - Tomas Mikoviny
- Department of Chemistry, University of Oslo, Oslo, Norway
| | - Kyung-Eun Min
- School of Earth Science and Environmental Engineering, Gwangju Institute of Science and Technology, Gwangju, South Korea
| | - Markus Müller
- Institute for Ion Physics and Applied Physics, University of Innsbruck, 6020 Innsbruck, Austria
| | - J. Andrew Neuman
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | | | - Jeff Peischl
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - Gabriele G. Pfister
- Atmospheric Chemistry Observations & Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - Dirk Richter
- Institute of Arctic & Alpine Research, University of Colorado, Boulder, CO, USA
| | - James M. Roberts
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - Thomas B. Ryerson
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - Stephen R. Shertz
- Atmospheric Chemistry Observations & Modeling Laboratory, National Center for Atmospheric Research, Boulder, CO, USA
| | - Chelsea R. Thompson
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - Victoria Treadaway
- Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, USA
| | - Patrick R. Veres
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - James Walega
- Institute of Arctic & Alpine Research, University of Colorado, Boulder, CO, USA
| | - Carsten Warneke
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | | | - Petter Weibring
- Institute of Arctic & Alpine Research, University of Colorado, Boulder, CO, USA
| | - Bin Yuan
- Institute for Environmental and Climate Research, Jinan University, Guangzhou, China
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Akob DM, Sutton JM, Fierst JL, Haase KB, Baesman S, Luther GW, Miller LG, Oremland RS. Acetylenotrophy: a hidden but ubiquitous microbial metabolism? FEMS Microbiol Ecol 2018; 94:5026170. [PMID: 29933435 PMCID: PMC7190893 DOI: 10.1093/femsec/fiy103] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 05/29/2018] [Indexed: 11/12/2022] Open
Abstract
Acetylene (IUPAC name: ethyne) is a colorless, gaseous hydrocarbon, composed of two triple bonded carbon atoms attached to hydrogens (C2H2). When microbiologists and biogeochemists think of acetylene, they immediately think of its use as an inhibitory compound of certain microbial processes and a tracer for nitrogen fixation. However, what is less widely known is that anaerobic and aerobic microorganisms can degrade acetylene, using it as a sole carbon and energy source and providing the basis of a microbial food web. Here, we review what is known about acetylene degrading organisms and introduce the term 'acetylenotrophs' to refer to the microorganisms that carry out this metabolic pathway. In addition, we review the known environmental sources of acetylene and postulate the presence of an hidden acetylene cycle. The abundance of bacteria capable of using acetylene and other alkynes as an energy and carbon source suggests that there are energy cycles present in the environment that are driven by acetylene and alkyne production and consumption that are isolated from atmospheric exchange. Acetylenotrophs may have developed to leverage the relatively high concentrations of acetylene in the pre-Cambrian atmosphere, evolving later to survive in specialized niches where acetylene and other alkynes were produced.
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Affiliation(s)
- Denise M Akob
- U. S. Geological Survey, 12201 Sunrise Valley Dr, MS 430, Reston, VA 20192 USA
| | - John M Sutton
- Department of Biological Sciences, The University of Alabama, SEC 2328, Box 870344, Tuscaloosa, AL 35487 USA
| | - Janna L Fierst
- Department of Biological Sciences, The University of Alabama, SEC 2328, Box 870344, Tuscaloosa, AL 35487 USA
| | - Karl B Haase
- U. S. Geological Survey, 12201 Sunrise Valley Dr, MS 430, Reston, VA 20192 USA
| | - Shaun Baesman
- U. S. Geological Survey, 345 Middlefield Road, MS 480, Menlo Park, CA 94025 USA
| | - George W Luther
- School of Marine Science and Policy, University of Delaware, 700 Pilottown Road, Cannon Laboratory 218, Lewes, DE 19958, USA
| | - Laurence G Miller
- U. S. Geological Survey, 345 Middlefield Road, MS 480, Menlo Park, CA 94025 USA
| | - Ronald S Oremland
- U. S. Geological Survey, 345 Middlefield Road, MS 480, Menlo Park, CA 94025 USA
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Akob DM, Baesman SM, Sutton JM, Fierst JL, Mumford AC, Shrestha Y, Poret-Peterson AT, Bennett S, Dunlap DS, Haase KB, Oremland RS. Detection of Diazotrophy in the Acetylene-Fermenting Anaerobe Pelobacter sp. Strain SFB93. Appl Environ Microbiol 2017; 83:e01198-17. [PMID: 28667109 DOI: 10.1128/AEM.01198-17] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Accepted: 06/23/2017] [Indexed: 01/05/2023] Open
Abstract
Acetylene (C2H2) is a trace constituent of the present Earth's oxidizing atmosphere, reflecting a mixture of terrestrial and marine emissions from anthropogenic, biomass-burning, and unidentified biogenic sources. Fermentation of acetylene was serendipitously discovered during C2H2 block assays of N2O reductase, and Pelobacter acetylenicus was shown to grow on C2H2 via acetylene hydratase (AH). AH is a W-containing, catabolic, low-redox-potential enzyme that, unlike nitrogenase (N2ase), is specific for acetylene. Acetylene fermentation is a rare metabolic process that is well characterized only in P. acetylenicus DSM3246 and DSM3247 and Pelobacter sp. strain SFB93. To better understand the genetic controls for AH activity, we sequenced the genomes of the three acetylene-fermenting Pelobacter strains. Genome assembly and annotation produced three novel genomes containing gene sequences for AH, with two copies being present in SFB93. In addition, gene sequences for all five compulsory genes for iron-molybdenum N2ase were also present in the three genomes, indicating the cooccurrence of two acetylene transformation pathways. Nitrogen fixation growth assays showed that DSM3426 could ferment acetylene in the absence of ammonium, but no ethylene was produced. However, SFB93 degraded acetylene and, in the absence of ammonium, produced ethylene, indicating an active N2ase. Diazotrophic growth was observed under N2 but not in experimental controls incubated under argon. SFB93 exhibits acetylene fermentation and nitrogen fixation, the only known biochemical mechanisms for acetylene transformation. Our results indicate complex interactions between N2ase and AH and suggest novel evolutionary pathways for these relic enzymes from early Earth to modern days.IMPORTANCE Here we show that a single Pelobacter strain can grow via acetylene fermentation and carry out nitrogen fixation, using the only two enzymes known to transform acetylene. These findings provide new insights into acetylene transformations and adaptations for nutrient (C and N) and energy acquisition by microorganisms. Enhanced understanding of acetylene transformations (i.e., extent, occurrence, and rates) in modern environments is important for the use of acetylene as a potential biomarker for extraterrestrial life and for degradation of anthropogenic contaminants.
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Cich MJ, Forthomme D, McRaven CP, Lopez GV, Hall GE, Sears TJ, Mantz AW. Temperature-dependent, nitrogen-perturbed line shape measurements in the ν1 + ν3 band of acetylene using a diode laser referenced to a frequency comb. J Phys Chem A 2013; 117:13908-18. [PMID: 24125088 DOI: 10.1021/jp408960e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The P(11) line of the ν1 + ν3 combination band of C2H2 was studied using an extended cavity diode laser locked to a frequency comb. Line shapes were measured for acetylene and nitrogen gas mixtures at a series of temperatures between 125 and 296 K and total pressures up to 1 atm. The data were fit to two speed-dependent line shape models and the results were compared. Line shape parameters were determined by simultaneously fitting data for all temperatures and pressures in a single multispectrum analysis. Earlier pure acetylene measurements [Cich et al. Appl. Phys. B 2012, 109, 373-38] were incorporated to account for self-perturbation. The resulting parameters reproduce the observed line shapes for the acetylene-nitrogen system over the range of temperatures and pressures studied with average root-mean-square observed-calculated errors of individual line measurement fits of approximately 0.01% of maximum transmission, close to the experimental signal-to-noise ratios. Errors in the pressure measurements constitute the major systematic errors in these measurements, and a statistical method is developed to quantify their effects on the line shape parameters for the present system.
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Affiliation(s)
- Matthew J Cich
- Department of Chemistry, Stony Brook University , Stony Brook, New York 11794, United States
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Metsälä M, Schmidt FM, Skyttä M, Vaittinen O, Halonen L. Acetylene in breath: background levels and real-time elimination kinetics after smoking. J Breath Res 2010; 4:046003. [DOI: 10.1088/1752-7155/4/4/046003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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11
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Didriche K, Lauzin C, Földes T, de Ghellinck D'Elseghem Vaernewijck X, Herman M. The FANTASIO+ set-up to investigate jet-cooled molecules: focus on overtone bands of the acetylene dimer. Mol Phys 2010. [DOI: 10.1080/00268976.2010.489525] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Pradhan M, Aziz MSI, Grilli R, Orr-Ewing AJ. Automated system for monitoring trace C2H2 in ambient air by cavity ring-down spectroscopy combined with sample preconcentration. Environ Sci Technol 2008; 42:7354-7359. [PMID: 18939570 DOI: 10.1021/es801378r] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A fully automated instrument combining a continuous wave cavity ring-down spectrometer and dual-trap sample preconcentration has been implemented for monitoring C2H2 mixing ratios in ambient air. A distributed feedback diode laser operating in the near-infrared region (lambda approximately 1534.973 nm in air) detects C2H2 in absorption via the P(17) rotational line of the (v1 + v3) vibrational combination band. The instrument is shown to be capable of fast, quantitative, and precise monitoring of C2H2 mixing ratios, with a detection limit of approximately 8 pptv (parts per trillion by volume). It thus has potential to be deployed for analysis of air samples in many rural and urban environments. In situ measurements were carried out at 30 min intervals over periods of up to 15 h on several days for indoor and outdoor air samples. For indoor air monitored on a Sunday, the C2H2 mixing ratio was stable at 1.45 +/- 0.04 ppbv (parts per billion by volume). On weekdays, both indoor and outside air analyses showed peaks in the range 2-4 ppbv in the early morning and late afternoon that coincided with periods of busy road traffic.
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Affiliation(s)
- Manik Pradhan
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK
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Oremland RS, Voytek MA. Acetylene as fast food: implications for development of life on anoxic primordial Earth and in the outer solar system. Astrobiology 2008; 8:45-58. [PMID: 18199006 DOI: 10.1089/ast.2007.0183] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Acetylene occurs, by photolysis of methane, in the atmospheres of jovian planets and Titan. In contrast, acetylene is only a trace component of Earth's current atmosphere. Nonetheless, a methane-rich atmosphere has been hypothesized for early Earth; this atmosphere would also have been rich in acetylene. This poses a paradox, because acetylene is a potent inhibitor of many key anaerobic microbial processes, including methanogenesis, anaerobic methane oxidation, nitrogen fixation, and hydrogen oxidation. Fermentation of acetylene was discovered approximately 25 years ago, and Pelobacter acetylenicus was shown to grow on acetylene by virtue of acetylene hydratase, which results in the formation of acetaldehyde. Acetaldehyde subsequently dismutates to ethanol and acetate (plus some hydrogen). However, acetylene hydratase is specific for acetylene and does not react with any analogous compounds. We hypothesize that microbes with acetylene hydratase played a key role in the evolution of Earth's early biosphere by exploiting an available source of carbon from the atmosphere and in so doing formed protective niches that allowed for other microbial processes to flourish. Furthermore, the presence of acetylene in the atmosphere of a planet or planetoid could possibly represent evidence for an extraterrestrial anaerobic ecosystem.
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15
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Abstract
Kinetics studies of the OH-initiated oxidation of 2-butyne, propyne, and acetylene were conducted at 100 Torr and 298 K using turbulent flow chemical ionization mass spectrometry. The major oxidation products were identified, and with the aid of supporting electronic structure thermodynamics calculations, a general OH-initiated oxidation mechanism for the alkynes is proposed. The major product branching ratio and the product-forming rate constants for the 2-butyne-OH adduct + O(2) reaction were experimentally determined as well. The atmospheric implications of the chemical oxidation mechanism and kinetics results are discussed.
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Affiliation(s)
- Laurence Y Yeung
- Department of Chemistry, Oberlin College, Oberlin, Ohio 44074, USA
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Kaspers KA. Analyses of firn gas samples from Dronning Maud Land, Antarctica: Study of nonmethane hydrocarbons and methyl chloride. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2003jd003950] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Mühle J. Air mass classification during the INDOEX R/VRonald Browncruise using measurements of nonmethane hydrocarbons, CH4, CO2, CO,14CO, and δ18O(CO). ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2001jd000730] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Gupta ML, Cicerone RJ, Blake DR, Rowland FS, Isaksen ISA. Global atmospheric distributions and source strengths of light hydrocarbons and tetrachloroethene. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98jd02645] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Gaudry A, Kanakidou M, Mihalopoulos N, Bonsang B, Bonsang G, Monfray P, Tymen G, Nguyen B. Atmospheric trace compounds at a European coastal site—application to CO2, CH4 and COS flux determinations. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/0960-1686(92)90267-o] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Bonsang B, Martin D, Lambert G, Kanakidou M, Le Roulley JC, Sennequier G. Vertical distribution of non methane hydrocarbons in the remote marine boundary layer. ACTA ACUST UNITED AC 1991. [DOI: 10.1029/90jd02539] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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