title: Changes in photosynthetic performance and antioxidative strategies during maturation of Norway maple (Acer platanoides L.) leaves.
abstract: Different structural and functional changes take place during leaf development. Since some of them are highly connected to oxidative metabolism, regulation of reactive oxygen species (ROS) abundance is required. Most of the reactive oxygen species ROS in plant cells are produced in chloroplasts as a result of highly energetic reactions of photosynthesis. The aim of our study was to examine the changes in concentration of oxidative stress parameters (TBARS - thiobarbituric acid-reacting substances and protein carbonyls) as well as antioxidative strategies during development of maple (Acer platanoides L.) leaves in the light of their enhanced photosynthetic performance. We reveal that biogenesis of the photosynthetic apparatus during maple leaf maturation corresponded with oxidative damage of lipids, but not proteins. In addition, antioxidative responses in young leaves differed from that in older leaves. Young leaves had high values of non-photochemical quenching (NPQ) and catalase (CAT, EC 1.11.1.6) activity which declined during the maturation process. Developing leaves were characterized by an increase in TBARS level, the content of non-enzymatic antioxidants as well as ascorbate peroxidase activity (APX, EC 1.11.1.11), while the content of protein carbonyls decreased with leaf maturation. Fully developed leaves had the highest lipid peroxidation level accompanied by a maximum in ascorbic acid content and superoxide dismutase activity (SOD, EC1.15.1.1). These observations imply completely different antioxidative strategies during leaf maturation enabling them to perform their basic function.
authors.affiliation: Agricultural Institute Osijek, Osijek, Croatia. hlepedus@yahoo.com
authors.forename: Hrvoje
authors.initials: H
authors.lastname: Lepeduš
authors.forename: Vlatka
authors.initials: V
authors.lastname: Gaća
authors.forename: Marija
authors.initials: M
authors.lastname: Viljevac
authors.forename: Spomenka
authors.initials: S
authors.lastname: Kovač
authors.forename: Hrvoje
authors.initials: H
authors.lastname: Fulgosi
authors.forename: Domagoj
authors.initials: D
authors.lastname: Simić
authors.forename: Vlatka
authors.initials: V
authors.lastname: Jurković
authors.forename: Vera
authors.initials: V
authors.lastname: Cesar
mesh_terms: D031002:Acer / Q000378:metabolism*; D000975:Antioxidants / Q000378:metabolism*; D060387:Ascorbate Peroxidases / Q000378:metabolism; D001205:Ascorbic Acid / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D045342:Light-Harvesting Protein Complexes / Q000378:metabolism; D015227:Lipid Peroxidation; D018384:Oxidative Stress; D010788:Photosynthesis; D045332:Photosystem II Protein Complex / Q000378:metabolism; D018515:Plant Leaves / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D050050:Protein Carbonylation; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
chemical_list: D000975:Antioxidants; D045342:Light-Harvesting Protein Complexes; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D017392:Thiobarbituric Acid Reactive Substances; D060387:Ascorbate Peroxidases; D002374:Catalase; D013482:Superoxide Dismutase; D001205:Ascorbic Acid