title: Arsenic hyperaccumulation induces metabolic reprogramming in Pityrogramma calomelanos to reduce oxidative stress.
abstract: Arsenic (As) pollution is a major environmental concern due to its worldwide distribution and high toxicity to organisms. The fern Pityrogramma calomelanos is one of the few plant species known to be able to hyperaccumulate As, although the mechanisms involved are largely unknown. This study aimed to investigate the metabolic adjustments involved in the As-tolerance of P. calomelanos. For this purpose, ferns with five to seven fronds were exposed to a series of As concentrations. Young fronds were used for biochemical analysis and metabolite profiling using gas chromatography-mass spectrometry. As treatment increased the total concentration of proteins and soluble phenols, enhanced peroxidase activities, and promoted disturbances in nitrogen and carbon metabolism. The reduction of the glucose pool was one of the striking responses to As. Remarkable changes in amino acids levels were observed in As-treated plants, including those related to biosynthesis of glutathione and phenols, osmoregulation and two photorespiratory intermediates. In addition, increases in polyamines levels and antioxidant enzyme activities were observed. In summary, this study indicates that P. calomelanos tolerates high concentration of As due to its capacity to upregulate biosynthesis of amino acids and antioxidants, without greatly disturbing central carbon metabolism. At extremely high As concentrations, however, this protective mechanism fails to block reactive oxygen species production, leading to lipid peroxidation and leaf necrosis.
authors: Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, 36570-900, Brazil.
authors: Naiara V
authors: NV
authors: Campos
authors: Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, 36570-900, Brazil.
authors: Talita O
authors: TO
authors: Araújo
authors: Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, 36570-900, Brazil.
authors: Samara
authors: S
authors: Arcanjo-Silva
authors: Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, 36570-900, Brazil.
authors: Larisse
authors: L
authors: Freitas-Silva
authors: Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, 36570-900, Brazil.
authors: Aristéa A
authors: AA
authors: Azevedo
authors: Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, 36570-900, Brazil.|Max-Planck Partner Group, Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, 36570-900, Brazil.
authors: Adriano
authors: A
authors: Nunes-Nesi
mesh_terms: D000596:Amino Acids / Q000096:biosynthesis; D000975:Antioxidants / Q000378:metabolism; D001151:Arsenic / Q000378:metabolism* / Q000633:toxicity; D001673:Biodegradation, Environmental; D015415:Biomarkers / Q000378:metabolism; D053898:Biosynthetic Pathways / Q000187:drug effects; D008401:Gas Chromatography-Mass Spectrometry; D018384:Oxidative Stress; D018515:Plant Leaves / Q000187:drug effects / Q000502:physiology; D029625:Pteridaceae / Q000187:drug effects / Q000502:physiology*; D012989:Soil Pollutants / Q000378:metabolism / Q000633:toxicity; D013312:Stress, Physiological
chemical_list: D000596:Amino Acids; D000975:Antioxidants; D015415:Biomarkers; D012989:Soil Pollutants; D001151:Arsenic