دورية أكاديمية

The operation of PEPCK increases light harvesting plasticity in C 4 NAD-ME and NADP-ME photosynthetic subtypes: A theoretical study.

التفاصيل البيبلوغرافية
العنوان: The operation of PEPCK increases light harvesting plasticity in C 4 NAD-ME and NADP-ME photosynthetic subtypes: A theoretical study.
المؤلفون: Bellasio C; Laboratory of Theoretical and Applied Crop Ecophysiology, School of Biology and Environmental Science, University College Dublin, Dublin, Ireland.; Department of Chemistry, Biology ond Biotechnology, Università Degli Studi Di Perugia, Perugia, Italy.; Department of Biology, University of the Balearic Islands, Palma, Illes Balears, Spain.; Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia., Lundgren MR; Lancaster Environment Centre, Lancaster University, Lancaster, UK.
المصدر: Plant, cell & environment [Plant Cell Environ] 2024 Jun; Vol. 47 (6), pp. 2288-2309. Date of Electronic Publication: 2024 Mar 18.
نوع المنشور: Journal Article; Research Support, Non-U.S. Gov't
اللغة: English
بيانات الدورية: Publisher: John Wiley & Sons Ltd Country of Publication: United States NLM ID: 9309004 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1365-3040 (Electronic) Linking ISSN: 01407791 NLM ISO Abbreviation: Plant Cell Environ Subsets: MEDLINE
أسماء مطبوعة: Publication: Hoboken, NJ : John Wiley & Sons Ltd.
Original Publication: Oxford, UK : Blackwell Scientific Publications
مواضيع طبية MeSH: Photosynthesis* , Malate Dehydrogenase*/metabolism, Light ; Phosphoenolpyruvate Carboxykinase (ATP)/metabolism ; Models, Biological
مستخلص: The repeated emergence of NADP-malic enzyme (ME), NAD-ME and phosphoenolpyruvate carboxykinase (PEPCK) subtypes of C 4 photosynthesis are iconic examples of convergent evolution, which suggests that these biochemistries do not randomly assemble, but are instead specific adaptations resulting from unknown evolutionary drivers. Theoretical studies that are based on the classic biochemical understanding have repeatedly proposed light-use efficiency as a possible benefit of the PEPCK subtype. However, quantum yield measurements do not support this idea. We explore this inconsistency here via an analytical model that features explicit descriptions across a seamless gradient between C 4 biochemistries to analyse light harvesting and dark photosynthetic metabolism. Our simulations show that the NADP-ME subtype, operated by the most productive crops, is the most efficient. The NAD-ME subtype has lower efficiency, but has greater light harvesting plasticity (the capacity to assimilate CO 2 in the broadest combination of light intensity and spectral qualities). In both NADP-ME and NAD-ME backgrounds, increasing PEPCK activity corresponds to greater light harvesting plasticity but likely imposed a reduction in photosynthetic efficiency. We draw the first mechanistic links between light harvesting and C 4 subtypes, providing the theoretical basis for future investigation.
(© 2024 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.)
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معلومات مُعتمدة: Ireland SFI_ Science Foundation Ireland
فهرسة مساهمة: Keywords: assimilation; dark reactions; grasses; light reactions; photosynthesis
المشرفين على المادة: EC 1.1.1.37 (Malate Dehydrogenase)
EC 1.1.1.40 (malate dehydrogenase (oxaloacetate-decarboxylating) (NADP+))
EC 4.1.1.49 (Phosphoenolpyruvate Carboxykinase (ATP))
EC 1.1.1.38 (malate dehydrogenase-(oxaloacetate-decarboxylating) (NAD+))
تواريخ الأحداث: Date Created: 20240318 Date Completed: 20240429 Latest Revision: 20240524
رمز التحديث: 20240525
DOI: 10.1111/pce.14869
PMID: 38494958
قاعدة البيانات: MEDLINE
الوصف
تدمد:1365-3040
DOI:10.1111/pce.14869