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Publications (10 of 20) Show all publications
Kumarathunge, D. P., Medlyn, B. E., Drake, J. E., Tjoelker, M. G., Aspinwall, M. J., Battaglia, M., . . . Way, D. A. (2019). Acclimation and adaptation components of the temperature dependence of plant photosynthesis at the global scale. New Phytologist, 222(2), 768-784
Open this publication in new window or tab >>Acclimation and adaptation components of the temperature dependence of plant photosynthesis at the global scale
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2019 (English)In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 222, no 2, p. 768-784Article in journal (Refereed) Published
Abstract [en]

The temperature response of photosynthesis is one of the key factors determining predicted responses to warming in global vegetation models (GVMs). The response may vary geographically, owing to genetic adaptation to climate, and temporally, as a result of acclimation to changes in ambient temperature. Our goal was to develop a robust quantitative global model representing acclimation and adaptation of photosynthetic temperature responses.

We quantified and modelled key mechanisms responsible for photosynthetic temperature acclimation and adaptation using a global dataset of photosynthetic CO2 response curves, including data from 141 C3 species from tropical rainforest to Arctic tundra. We separated temperature acclimation and adaptation processes by considering seasonal and common-garden datasets, respectively.

The observed global variation in the temperature optimum of photosynthesis was primarily explained by biochemical limitations to photosynthesis, rather than stomatal conductance or respiration. We found acclimation to growth temperature to be a stronger driver of this variation than adaptation to temperature at climate of origin.

We developed a summary model to represent photosynthetic temperature responses and showed that it predicted the observed global variation in optimal temperatures with high accuracy. This novel algorithm should enable improved prediction of the function of global ecosystems in a warming climate.

Place, publisher, year, edition, pages
John Wiley & Sons, 2019
Keywords
ACi curves, Climate of origin, Global vegetation models (GVMs), Growth temperature, Jmax, Maximum carboxylation capacity, Maximum electron transport rate, Vcmax
National Category
Climate Research
Research subject
Natural Science, Environmental Science; Technology (byts ev till Engineering), Forestry and Wood Technology
Identifiers
urn:nbn:se:lnu:diva-81063 (URN)10.1111/nph.15668 (DOI)000465446300016 ()30597597 (PubMedID)2-s2.0-85061240700 (Scopus ID)
Available from: 2019-03-13 Created: 2019-03-13 Last updated: 2019-08-29Bibliographically approved
Jensen, A. M., Warren, J. M., King, A. W., Ricciuto,, D. M., Hanson, P. J. & Wullschleger, S. D. (2019). Simulated projections of boreal forest peatland ecosystem productivity are sensitive to observed seasonality in leaf physiology. Tree Physiology, 39(4), 556-572
Open this publication in new window or tab >>Simulated projections of boreal forest peatland ecosystem productivity are sensitive to observed seasonality in leaf physiology
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2019 (English)In: Tree Physiology, ISSN 0829-318X, E-ISSN 1758-4469, Vol. 39, no 4, p. 556-572Article in journal (Refereed) Published
Abstract [en]

We quantified seasonal CO2 assimilation capacities for seven dominant vascular species in a wet boreal forest peatland then applied data to a land surface model parametrized to the site (ELM-SPRUCE) to test if seasonality in photosynthetic parameters results in differences in simulated plant responses to elevated CO2 and temperature. We collected seasonal leaf-level gas exchange, nutrient content and stand allometric data from the field-layer community (i.e., Maianthemum trifolium (L.) Sloboda), understory shrubs (Rhododendron groenlandicum (Oeder) Kron and Judd, Chamaedaphne calyculata (L.) Moench., Kalmia polifolia Wangenh. and Vaccinium angustifolium Alton.) and overstory trees (Picea mariana (Mill.) B.S.P. and Larix laricina (Du Roi) K. Koch). We found significant interspecific seasonal differences in specific leaf area, nitrogen content (by area; Na) and photosynthetic parameters (i.e., maximum rates of Rubisco carboxylation (Vcmax25°C), electron transport (Jmax25°C) and dark respiration (Rd25°C)), but minimal correlation between foliar Na and Vcmax25°C, Jmax25°C or Rd25°C, which illustrates that nitrogen alone is not a good correlate for physiological processes such as Rubisco activity that can change seasonally in this system. ELM-SPRUCE was sensitive to the introduction of observed interspecific seasonality in Vcmax25°C, Jmax25°C and Rd25°C, leading to simulated enhancement of net primary production (NPP) using seasonally dynamic parameters as compared with use of static parameters. This pattern was particularly pronounced under simulations with higher temperature and elevated CO2, suggesting a key hypothesis to address with future empirical or observational studies as climate changes. Inclusion of species-specific seasonal photosynthetic parameters should improve estimates of boreal ecosystem-level NPP, especially if impacts of seasonal physiological ontogeny can be separated from seasonal thermal acclimation.

Place, publisher, year, edition, pages
Oxford University Press, 2019
National Category
Forest Science
Research subject
Natural Science, Ecology; Technology (byts ev till Engineering), Forestry and Wood Technology
Identifiers
urn:nbn:se:lnu:diva-79021 (URN)10.1093/treephys/tpy140 (DOI)
Available from: 2018-11-29 Created: 2018-11-29 Last updated: 2019-08-28Bibliographically approved
Furze, M. E., Jensen, A. M., Warren, J. & Richardson, R. (2018). Seasonal patterns of nonstructural carbohydrate reserves in four woody boreal species. Journal of the Torrey Botanical Society, 145(4), 332-339
Open this publication in new window or tab >>Seasonal patterns of nonstructural carbohydrate reserves in four woody boreal species
2018 (English)In: Journal of the Torrey Botanical Society, ISSN 1095-5674, E-ISSN 1940-0616, Vol. 145, no 4, p. 332-339Article in journal (Refereed) Published
Abstract [en]

Plants store nonstructural carbohydrates (NSCs), such as sugars and starch, to use as carbon and energy sources for daily maintenance and growth needs as well as during times of stress. Allocation of NSCs to storage provides an important physiological strategy associated with future growth and survival, and thus understanding the seasonal patterns of NSC reserves provides insight into how species with different traits (e.g., growth form, leaf habit, wood anatomy) may respond to stress. We characterized the seasonal patterns of NSCs in four woody boreal plant species in Minnesota, USA. Sugar and starch concentrations were measured across the year in the roots and branches of two conifer trees, black spruce (Picea mariana (Mill.) B.S.P.) and eastern tamarack (Larix laricina (Du Roi) K. Koch), as well as in the leaves and branches of two evergreen broadleaf shrubs, bog Labrador tea (Rhododendron groenlandicum (Oeder) Kron & Judd) and leatherleaf (Chamaedaphne calyculata (L.) Moench). In general, seasonal variation was dominated by changes in starch across all organs and species. While similar seasonal patterns of NSCs were observed in the shrubs, different seasonal patterns were observed between the trees, particularly in the roots. Our results suggest that species-specific traits likely have consequences for organ-level storage dynamics, which may influence whole-plant growth and survival under global change

Keywords
boreal, carbohydrates, carbon allocation, NSC, SPRUCE
National Category
Ecology
Research subject
Natural Science, Ecology
Identifiers
urn:nbn:se:lnu:diva-79020 (URN)10.3159/TORREY-D-18-00007.1 (DOI)
Available from: 2018-11-29 Created: 2018-11-29 Last updated: 2018-12-04Bibliographically approved
Jensen, A. M. & Löf, M. (2017). Effects of interspecific competition from surrounding vegetation on mortality, growth and stem development in young oaks (Quercus robur). Forest Ecology and Management, 392, 176-183
Open this publication in new window or tab >>Effects of interspecific competition from surrounding vegetation on mortality, growth and stem development in young oaks (Quercus robur)
2017 (English)In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 392, p. 176-183Article in journal (Refereed) Published
Abstract [en]

Facilitation by a neighboring woody understory has been suggested as a cost-effective and sustainable way to regenerate oaks. However, concerns about reduced plant growth and quality due to competing neighboring vegetation have hindered implementation. Here we studied competitive effects from herbaceous and woody vegetation on survival, growth, canopy development and stem quality in pedunculate oak (Quercus robur) in an open-field experiment in southern Sweden. Oaks were grown for eight years in four different competition treatments: no competing vegetation, with herbaceous vegetation (mainly grasses), with woody vegetation, and with both herbaceous and woody vegetation. During the first four years, competition had little effect on oak survival. However, after eight growing seasons, survival rates decreased to about 20% for oaks surrounded by woody vegetation, in contrast to oaks grown with only herbaceous vegetation that had a survival rate of near 100%. Competition from herbaceous and woody vegetation both reduced oak stem diameter and height growth, but they affected height growth differently. During the first growing seasons, oaks in the treatment with woody vegetation were able to keep up with the height growth of the surrounding vegetation. Thereafter, height growth stagnated, and after eight growing seasons heights of oaks in the treatment with woody competitors were only 30–39% that of oaks in the treatment without competing vegetation. In contrast, competition from herbaceous vegetation only restricted oak height development marginally. Interspecific competition not only restricted growth and survival but also shifted shoot architecture, resulting in a greater frequency of oaks with straight monopodial stems. Although competition from both herbaceous- and woody vegetation positively affected stem straightness, plots with woody vegetation had a greater proportion (0.42) of oaks with a single straight monopodial stem. Our results demonstrate that the facilitative competitive effects from herbaceous and woody vegetation could be used to control allocation patterns in young oaks, promoting development of tall straight monopodial stems. Considering the observed trade-off between high stem quality and survival, we recommend long-term assessment of this trade-off prior to application in practical forestry.

Place, publisher, year, edition, pages
Elsevier, 2017
Keywords
Stem curvature; Plant-plant interactions; Competition; Understory
National Category
Forest Science Ecology Botany
Research subject
Technology (byts ev till Engineering), Forestry and Wood Technology
Identifiers
urn:nbn:se:lnu:diva-61597 (URN)10.1016/j.foreco.2017.03.009 (DOI)000400201900017 ()2-s2.0-85015042790 (Scopus ID)
Available from: 2017-03-21 Created: 2017-03-21 Last updated: 2019-08-29Bibliographically approved
Norby, R. J., Gu, L., Haworth, I. C., Jensen, A. M., Turner, B. L., Walker, A. P., . . . Winter, K. (2017). Informing models through empirical relationships between foliar phosphorus, nitrogen and photosynthesis across diverse woody species in tropical forests of Panama. New Phytologist, 215(4), 1425-1437
Open this publication in new window or tab >>Informing models through empirical relationships between foliar phosphorus, nitrogen and photosynthesis across diverse woody species in tropical forests of Panama
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2017 (English)In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 215, no 4, p. 1425-1437Article in journal (Refereed) Published
Abstract [en]

Our objective was to analyze and summarize data describing photosynthetic parameters and foliar nutrient concentrations from tropical forests in Panama to inform model representation of phosphorus (P) limitation of tropical forest productivity.

Gas exchange and nutrient content data were collected from 144 observations of upper canopy leaves from at least 65 species at two forest sites in Panama, differing in species composition, rainfall and soil fertility. Photosynthetic parameters were derived from analysis of assimilation rate vs internal CO2 concentration curves (A/Ci), and relationships with foliar nitrogen (N) and P content were developed.

The relationships between area-based photosynthetic parameters and nutrients were of similar strength for N and P and robust across diverse species and site conditions. The strongest relationship expressed maximum electron transport rate (Jmax) as a multivariate function of both N and P, and this relationship was improved with the inclusion of independent data on wood density.

Models that estimate photosynthesis from foliar N would be improved only modestly by including additional data on foliar P, but doing so may increase the capability of models to predict future conditions in P-limited tropical forests, especially when combined with data on edaphic conditions and other environmental drivers.

Place, publisher, year, edition, pages
Wiley-Blackwell, 2017
National Category
Forest Science
Research subject
Technology (byts ev till Engineering), Forestry and Wood Technology
Identifiers
urn:nbn:se:lnu:diva-56988 (URN)10.1111/nph.14319 (DOI)000406876700015 ()2-s2.0-85005847155 (Scopus ID)
Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2019-08-29Bibliographically approved
Griffiths, N. A., Hanson, P. J., Ricciuto, D. M., Iversen, C. M., Jensen, A. M., Malhotra, A., . . . Weston, D. J. (2017). Temporal and Spatial Variation in Peatland Carbon Cycling and Implications for Interpreting Responses of an Ecosystem-Scale Warming Experiment. Soil Science Society of America Journal, 81(6), 1668-1688
Open this publication in new window or tab >>Temporal and Spatial Variation in Peatland Carbon Cycling and Implications for Interpreting Responses of an Ecosystem-Scale Warming Experiment
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2017 (English)In: Soil Science Society of America Journal, ISSN 0361-5995, E-ISSN 1435-0661, Vol. 81, no 6, p. 1668-1688Article in journal (Refereed) Published
Abstract [en]

We are conducting a large-scale, long-term climate change response experiment in an ombrotrophic peat bog in Minnesota to evaluate the effects of warming and elevated CO2 on ecosystem processes using empirical and modeling approaches. To better frame future assessments of peatland responses to climate change, we characterized and compared spatial vs. temporal variation in measured C cycle processes and their environmental drivers. We also conducted a sensitivity analysis of a peatland C model to identify how variation in ecosystem parameters contributes to model prediction uncertainty. High spatial variability in C cycle processes resulted in the inability to determine if the bog was a C source or sink, as the 95% confidence interval ranged from a source of 50 g C m(-2) yr(-1) to a sink of 67 g C m(-2) yr(-1). Model sensitivity analysis also identified that spatial variation in tree and shrub photosynthesis, allocation characteristics, and maintenance respiration all contributed to large variations in the pretreatment estimates of net C balance. Variation in ecosystem processes can be more thoroughly characterized if more measurements are collected for parameters that are highly variable over space and time, and especially if those measurements encompass environmental gradients that may be driving the spatial and temporal variation (e.g., hummock vs. hollow microtopographies, and wet vs. dry years). Together, the coupled modeling and empirical approaches indicate that variability in C cycle processes and their drivers must be taken into account when interpreting the significance of experimental warming and elevated CO2 treatments.

Place, publisher, year, edition, pages
ACSESS, 2017
National Category
Climate Research
Research subject
Technology (byts ev till Engineering), Forestry and Wood Technology; Natural Science, Environmental Science
Identifiers
urn:nbn:se:lnu:diva-70251 (URN)10.2136/sssaj2016.12.0422 (DOI)000419646100041 ()2-s2.0-85040638144 (Scopus ID)
Available from: 2018-01-30 Created: 2018-01-30 Last updated: 2019-09-09Bibliographically approved
Götmark, F., Götmark, E. & Jensen, A. M. (2016). Why Be a Shrub?: a Basic Model and Hypotheses for the Adaptive Values of a Common Growth Form. Frontiers in Plant Science, 7, Article ID 1095.
Open this publication in new window or tab >>Why Be a Shrub?: a Basic Model and Hypotheses for the Adaptive Values of a Common Growth Form
2016 (English)In: Frontiers in Plant Science, ISSN 1664-462X, E-ISSN 1664-462X, Vol. 7, article id 1095Article in journal (Refereed) Published
Abstract [en]

Shrubs are multi-stemmed short woody plants, more widespread than trees, important in many ecosystems, neglected in ecology compared to herbs and trees, but currently in focus due to their global expansion. We present a novel model based on scaling relationships and four hypotheses to explain the adaptive significance of shrubs, including a review of the literature with a test of one hypothesis. Our model describes advantages for a small shrub compared to a small tree with the same above-ground woody volume, based on larger cross-sectional stem area, larger area of photosynthetic tissue in bark and stem, larger vascular cambium area, larger epidermis (bark) area, and larger area for sprouting, and faster production of twigs and canopy. These components form our Hypothesis 1 that predicts higher growth rate for a small shrub than a small tree. This prediction was supported by available relevant empirical studies (14 publications). Further, a shrub will produce seeds faster than a tree (Hypothesis 2), multiple stems in shrubs insure future survival and growth if one or more stems die (Hypothesis 3), and three structural traits of short shrub stems improve survival compared to tall tree stems (Hypothesis 4)—all hypotheses have some empirical support. Multi-stemmed trees may be distinguished from shrubs by more upright stems, reducing bending moment. Improved understanding of shrubs can clarify their recent expansion on savannas, grasslands, and alpine heaths. More experiments and other empirical studies, followed by more elaborate models, are needed to understand why the shrub growth form is successful in many habitats.

National Category
Ecology
Research subject
Natural Science, Ecology
Identifiers
urn:nbn:se:lnu:diva-55089 (URN)10.3389/fpls.2016.01095 (DOI)000380221600001 ()27507981 (PubMedID)2-s2.0-84979736742 (Scopus ID)
Available from: 2016-07-28 Created: 2016-07-28 Last updated: 2019-06-25Bibliographically approved
Warren, J. M., Jensen, A. M., Medlyn, B. E., Norby, R. J. & Tissue, D. T. (2015). Carbon dioxide stimulation of photosynthesis in Liquidambar styraciflua is not sustained during a 12-year field experiment. AoB Plants, 7, Article ID plu074.
Open this publication in new window or tab >>Carbon dioxide stimulation of photosynthesis in Liquidambar styraciflua is not sustained during a 12-year field experiment
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2015 (English)In: AoB Plants, ISSN 2041-2851, E-ISSN 2041-2851, Vol. 7, article id plu074Article in journal (Refereed) Published
Abstract [en]

Elevated atmospheric CO2 (eCO2) often increases photosynthetic CO2assimilation (A) in field studies of temperate tree species. However, there is evidence that A may decline through time due to biochemical and morphological acclimation, and environmental constraints. Indeed, at the free-air CO2 enrichment (FACE) study in Oak Ridge, Tennessee, A was increased in 12-year-old sweetgum trees following 2 years of ∼40 % enhancement of CO2A was re-assessed a decade later to determine if the initial enhancement of photosynthesis by eCO2 was sustained through time. Measurements were conducted at prevailing CO2 and temperature on detached, re-hydrated branches using a portable gas exchange system. Photosynthetic CO2 response curves (A versus the CO2 concentration in the intercellular air space (Ci); or ACi curves) were contrasted with earlier measurements using leaf photosynthesis model equations. Relationships between light-saturated photosynthesis (Asat), maximum electron transport rate (Jmax), maximum Rubisco activity (Vcmax), chlorophyll content and foliar nitrogen (N) were assessed. In 1999, Asat for eCO2treatments was 15.4 ± 0.8 μmol m−2 s−1, 22 % higher than aCO2treatments (P < 0.01). By 2009, Asat declined to <50 % of 1999 values, and there was no longer a significant effect of eCO2 (Asat = 6.9 or 5.7 ± 0.7 μmol m−2 s−1 for eCO2 or aCO2, respectively). In 1999, there was no treatment effect on area-based foliar N; however, by 2008, N content in eCO2 foliage was 17 % less than that in aCO2 foliage. Photosynthetic N-use efficiency (Asat : N) was greater in eCO2 in 1999 resulting in greaterAsat despite similar N content, but the enhanced efficiency in eCO2 trees was lost as foliar N declined to sub-optimal levels. There was no treatment difference in the declining linear relationships between Jmax or Vcmax with declining N, or in the ratio of Jmax : Vcmax through time. Results suggest that the initial enhancement of photosynthesis to elevated CO2 will not be sustained through time if N becomes limited.

Place, publisher, year, edition, pages
Oxford University Press, 2015
Keywords
Acclimation, down-regulation, free-air CO2 enrichment, nitrogen limitation, sweetgum
National Category
Botany
Research subject
Technology (byts ev till Engineering), Forestry and Wood Technology
Identifiers
urn:nbn:se:lnu:diva-41891 (URN)10.1093/aobpla/plu074 (DOI)
Projects
ORNL -FACE
Available from: 2015-04-08 Created: 2015-04-08 Last updated: 2019-05-20Bibliographically approved
Jensen, A. M., Warren, J. M., Hanson, P., Childs, J. & Wullschleger, S. (2015). Needle age and season influence photosynthetic temperature response and total annual carbon uptake in mature Picea mariana trees. Annals of Botany, 116(5), 821-832
Open this publication in new window or tab >>Needle age and season influence photosynthetic temperature response and total annual carbon uptake in mature Picea mariana trees
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2015 (English)In: Annals of Botany, ISSN 0305-7364, E-ISSN 1095-8290, Vol. 116, no 5, p. 821-832Article in journal (Refereed) Published
Abstract [en]

Background, Aims and Methods; The carbon (C) balance of boreal terrestrial ecosystems is sensitive to increasing temperature, but the direction and thresholds of responses are uncertain. Annual C uptake in Picea and other evergreen boreal conifers is dependent on seasonal- and cohort-specific photosynthetic and respiratory temperature response functions. To assess the physiological significance of maintaining multiple foliar cohorts we measured photosynthetic capacity, foliar respiration (Rd), and leaf biochemistry and morphology of mature Picea mariana trees within an ombrotrophic bog ecosystem in Minnesota, USA. Results were applied to a simple model of canopy photosynthesis to simulate annual C uptake by cohort age under ambient and elevated temperature scenarios.

Key Results; Temperature responses of key photosynthetic parameters (i.e., light-saturated rate of CO2 assimilation (Asat), rate of Rubisco carboxylation (Vcmax), electron transport rate (Jmax)) were dependent on season and generally less responsive in the developing current-year (Y0) needles compared to one-year-old (Y1) or two-year-old (Y2) foliage. Temperature optimums ranged from 18.7 - 23.7, 31.3 - 38.3 and 28.7 - 36.7°C for Asat, Vcmax and Jmax, respectively. Foliar cohorts differed in their morphology and photosynthetic capacity, which resulted in 64% of modeled annual stand C uptake from Y1&2 cohorts (LAI 0.67 m2 m-2) and just 36% from the Y0 cohorts (LAI 0.52 m2 m-2). Under warmer climate change scenarios, the contribution of Y0 cohorts was even less; e.g., 31% of annual C uptake for a modeled 9°C rise in mean summer temperatures. Results suggest that net annual C uptake by P. mariana could increase under elevated temperature, and become more dependent on older foliar cohorts.

Conclusions; Collectively, these results illustrate the physiological and ecological significance of different foliar cohorts, and indicate the need for seasonal- and cohort-specific model parameterization when estimating C uptake capacity of boreal forest ecosystems under ambient or future temperature scenarios.

Keywords
Black spruce; temperature adjustment; carbon assimilation; A/Ci curve; leaf age; Q10; evergreen; SPRUCE project; STELLA model; respiration
National Category
Botany Forest Science
Research subject
Technology (byts ev till Engineering), Forestry and Wood Technology
Identifiers
urn:nbn:se:lnu:diva-45008 (URN)10.1093/aob/mcv115 (DOI)000362842400015 ()
Projects
“Spruce and Peatland Responses Under Climatic and Environmental Change” (SPRUCE; http://mnspruce.ornl.gov/).
Available from: 2015-06-23 Created: 2015-06-23 Last updated: 2019-05-20Bibliographically approved
Hao, M.-S., Jensen, A. M., Boquist, A.-S., Liu, Y.-J. & Rasmusson, A. G. (2015). The Ca2+-Regulation of the Mitochondrial External NADPH Dehydrogenase in Plants Is Controlled by Cytosolic pH. PLoS ONE, 10(9), Article ID e0139224.
Open this publication in new window or tab >>The Ca2+-Regulation of the Mitochondrial External NADPH Dehydrogenase in Plants Is Controlled by Cytosolic pH
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2015 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, no 9, article id e0139224Article in journal (Refereed) Published
Abstract [en]

NADPH is a key reductant carrier that maintains internal redox and antioxidant status, and that links biosynthetic, catabolic and signalling pathways. Plants have a mitochondrial external NADPH oxidation pathway, which depends on Ca2+ and pH in vitro, but concentrations of Ca2+ needed are not known. We have determined the K-0.5(Ca2+) of the external NADPH dehydrogenase from Solanum tuberosum mitochondria and membranes of E. coli expressing Arabidopsis thaliana NDB1 over the physiological pH range using O-2 and decylubiquinone as electron acceptors. The K-0.5(Ca2+) of NADPH oxidation was generally higher than for NADH oxidation, and unlike the latter, it depended on pH. At pH 7.5, K-0.5(Ca2+) for NADPH oxidation was high (approximate to 100 mu M), yet 20-fold lower K-0.5(Ca2+) values were determined at pH 6.8. Lower K-0.5(Ca2+) values were observed with decylubiquinone than with O-2 as terminal electron acceptor. NADPH oxidation responded to changes in Ca2+ concentrations more rapidly than NADH oxidation did. Thus, cytosolic acidification is an important activator of external NADPH oxidation, by decreasing the Ca2+-requirements for NDB1. The results are discussed in relation to the present knowledge on how whole cell NADPH redox homeostasis is affected in plants modified for the NDB1 gene.

National Category
Biological Sciences
Research subject
Technology (byts ev till Engineering), Forestry and Wood Technology
Identifiers
urn:nbn:se:lnu:diva-46901 (URN)10.1371/journal.pone.0139224 (DOI)000362170700050 ()26413894 (PubMedID)2-s2.0-84946935131 (Scopus ID)
Available from: 2015-10-26 Created: 2015-10-26 Last updated: 2019-05-20Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-5113-5624

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