Plant respiration under low oxygen

Abstract

Respiration is an oxidative process controlled by three pathways: glycolysis, the tricarboxylic acid (TCA) cycle, and oxidative phosphorylation (OXPHOS). Respiratory metabolism is ubiquitous in all organisms, but with differences among each other. For example in plants, because their high plasticity, respiration involves metabolic pathways with unique characteristics. In this way, in order to avoid states of low energy availability, plants exhibit great flexibility to bypass conventional steps of glycolysis, TCA cycle, and OXPHOS. To understand the energetic link between these alternative pathways, it is important to know the growth, maintenance, and ion uptake components of the respiration in plants. Changes in these components have been reported when plants are subjected to stress, such as oxygen deficiency. This review analyzes the current knowledge on the metabolic and functional aspects of plant respiration, its components and its response to environmental changes.

Integrated proteomic and metabolomic analyses revealed molecular adjustments in Populus × canescens colonized with the ectomycorrhizal fungus Paxillus involutus, which limited plant host growth

“…Mitochondrial isocitrate dehydrogenase was less abundant in the M roots than in the NM roots, but malate dehydrogenase, citrate synthase and citrate were more abundant. Decreased levels of succinate [a metabolite linking the TCA cycle with the mitochondrial electron transport chain (mitEC)] and most of the detected mitEC enzymes and various ATPases were detected in M roots, together with decreased concentrations of acetate and alanine (major products of cellular fermentation formed directly from pyruvate; Toro and Pinto, 2015). All the detected differences in glycolysis and TCA function were strongly reflected in the protein COG class abundance (Fig.…”

Glycolysis Fermentative By-Products and Secondary Metabolites Involved in Plant Adaptation under Hypoxia during Pre- and Postharvest

“…Gas diffusion in the air is 10,000 times faster than in water when O 2 diffuses at the rate of 0.201 cm −2 s −1 in air, compared to 2.1 × 10 −5 cm −2 s −1 in water [2]. The O 2 available level will affect plant cellular metabolisms in three different levels ( Table 1, [3]):…”

Insights into rootstock biology under low oxygen

“…A decrease in soil oxygen diffusion induces anatomical, physiological, and molecular changes in roots and aerial parts of a plant. This affects processes such as nutrient and water uptake, and particularly root respiration (Toro and Pinto, 2015). Salazar et al (2015) analyze changes in gene expression associated with pathways that are not present under normal oxygen supply.…”

“…The major physiological responses to hypoxia stress conditions are mainly associated with reduced root respiration. This is analyzed by Toro and Pinto (2015), who describe the characteristics of the plant respiratory process, particularly under stress. Reduced respiration means low availability of metabolic energy (ATP) and carbon chains for growth processes (new compound biosynthesis).…”