title: Effects of water turbulence on variations in cell ultrastructure and metabolism of amino acids in the submersed macrophyte, Elodea nuttallii (Planch.) H. St. John.
abstract: The interactions between macrophytes and water movement are not yet fully understood, and the causes responsible for the metabolic and ultrastructural variations in plant cells as a consequence of turbulence are largely unknown. In the present study, growth, metabolism and ultrastructural changes were evaluated in the aquatic macrophyte Elodea nuttallii, after exposure to turbulence for 30 days. The turbulence was generated with a vertically oscillating horizontal grid. The turbulence reduced plant growth, plasmolysed leaf cells and strengthened cell walls, and plants exposed to turbulence accumulated starch granules in stem chloroplasts. The size of the starch granules increased with the magnitude of the turbulence. Using capillary electrophoresis-mass spectrometry (CE-MS), analysis of the metabolome found metabolite accumulation in response to the turbulence. Asparagine was the dominant amino acid that was concentrated in stressed plants, and organic acids such as citrate, ascorbate, oxalate and γ-amino butyric acid (GABA) also accumulated in response to turbulence. These results indicate that turbulence caused severe stress that affected plant growth, cell ultrastructure and some metabolic functions of E. nuttallii. Our findings offer insights to explain the effects of water movement on the functions of aquatic plants.
authors.affiliation: Department of Environmental Science and Technology, Saitama University, Sakura-Ku, Saitama, Japan.
authors.forename: K S S
authors.initials: KS
authors.lastname: Atapaththu
authors.affiliation: Department of Environmental Science and Technology, Saitama University, Sakura-Ku, Saitama, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Miyagi
authors.affiliation: Comprehensive Analysis Center for Science, Saitama University, Sakura-Ku, Saitama, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Atsuzawa
authors.affiliation: Biology Section in the Faculty of Education, Graduate School of Science and Engineering, Saitama University, Sakura-Ku, Saitama, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kaneko
authors.affiliation: Department of Environmental Science and Technology, Saitama University, Sakura-Ku, Saitama, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Kawai-Yamada
authors.affiliation: Department of Environmental Science and Technology, Saitama University, Sakura-Ku, Saitama, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Asaeda
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D001216:Asparagine / Q000378:metabolism; D002736:Chloroplasts / Q000378:metabolism; D019075:Electrophoresis, Capillary; D031321:Hydrocharitaceae / Q000502:physiology* / Q000648:ultrastructure; D013058:Mass Spectrometry; D053858:Metabolic Networks and Pathways; D018547:Plant Stems / Q000502:physiology / Q000648:ultrastructure; D013213:Starch / Q000378:metabolism; D013312:Stress, Physiological; D014867:Water / Q000502:physiology*; D014872:Water Movements
chemical_list: D000596:Amino Acids; D014867:Water; D001216:Asparagine; D013213:Starch
keywords: Amino acids; Elodea nuttallii; asparagine; starch granules; turbulence