An off-line implementation of the stable isotope technique for measurements of alternative respiratory pathway activities

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Nagel, O.W. ; Waldron, S. ; Jones, H.G. (2001)
  • Publisher: American Society of Plant Biologists
  • Subject: QK

In situ measurements of alternative respiratory pathway activity are needed to provide insight into the energy efficiency of plant metabolism under various conditions in the field. The only reliable method at present to measure alternative oxidase (AOX) activity is through measurement of changes in delta O-18(O-2), which to date has only been used in laboratory environments. We have developed a cuvette system to measure partitioning of electrons to AOX that is suitable for off-line use and for field experiments. Plant samples are enclosed in airtight cuvettes and O-2 consumption is monitored. Gas samples from the cuvette are stored in evacuated gas containers until measurement of delta O-18(O-2). We have validated this method using differing plant material to assess AOX activity. Fractionation factors were calculated from delta O-18(O-2) measurements, which could be measured with an accuracy and precision to 0.1 parts per thousand and 0.3 parts per thousand respectively. Potential sources of error are discussed and quantified. Our method provides results similar to those obtained with laboratory incubations on-line to a mass spectrometer but greatly increases the potential for adoption of the stable isotope method.
  • References (35)
    35 references, page 1 of 4

    Angert A, Luz B (2001) Fractionation of oxygen isotopes by root respiration: implications for the isotopic composition of atmospheric O2. Geochim Cosmochim Acta 65: 1695-1701

    Atkin OK, Cummins WR, Collier DE (1993) Light induction of alternative pathway capacity in leaf slices of Belgium endive. Plant Cell Environ 16: 231-235

    Azco´ n-Bieto J, Lambers H, Day DA (1983) Effect of photosynthesis and carbohydrate status on respiratory rates and the involvement of the alternative pathway in leaf respiration. Plant Physiol 72: 598-603

    Bottinga Y, Craig H (1969) Oxygen isotope fractionation between CO2 and water, and the isotopic composition of marine atmospheric CO2. Earth Planet Sci Lett 5: 285-295

    Collier DE, Cummins WR (1992) Stimulation of respiration during plant water deficits in sand-grown Arnica alpina. In H Lambers, LHW Van der Plas, eds, Biochemical and Physiological Aspects of Plant Respiration. SPB Academic Publishing bv, The Hague, The Netherlands, pp 541-546

    Drake BG, Azco´ n-Bieto J, Berry J, Bunce J, Dijkstra P, Farrar J, Gifford RM, Gonza`lez-Meler MA, Koch G, Lambers H et al. (1999) Does elevated atmospheric CO2 concentration inhibit mitochondrial respiration in green plants? Plant Cell Environ 22: 649-657

    Gale J, Reuveni J, Mayer AM (1992) An oxygen gradient method for determining the partitioning of respiration between its cytochrome and alternative pathway components, with application to Lemna gibba fronds under different temperatures. In H Lambers, LHW Van der Plas, eds, Biochemical and Physiological Aspects of Plant Respiration. SPB Academic Publishing bv, The Hague, The Netherlands, pp 433-442

    Gonza`lez-Meler MA, Giles L, Thomas RB, Siedow JN (2001) Metabolic regulation of leaf respiration and alternative pathway activity in response to phosphate supply. Plant Cell Environ 24: 205-215

    Gonza`lez-Meler MA, Ribas-Carbo M, Giles L, Siedow JN (1999) The effect of growth and measurement temperature on the activity of the alternative respiratory pathway. Plant Physiol 120: 765-772

    Gonza`lez-Meler MA, Ribas-Carbo M, Siedow JN, Drake BG (1996) Direct inhibition of plant mitochondrial respiration by elevated CO2. Plant Physiol 112: 1349-1355

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