Photochemical and non-photochemical energy dissipation in response to 5-aminolaevulinic acid-induced photosensitization of green leaves of wheat (Triticum aestivum L) and lettuce (Lactuca sativa L)

被引:6
作者
Hartel, H
Walter, G
Haseloff, RF
Hoffmann, P
Renger, G
机构
[1] FORSCHUNGSINST MOL PHARMAKOL,D-10315 BERLIN,GERMANY
[2] TECH UNIV BERLIN,MAX VOLMER INST BIOPHYS & PHYS CHEM,D-10623 BERLIN,GERMANY
关键词
5-aminolaevulinic acid; chlorophyll fluorescence quenching; free radicals; Mehler reaction; photosensitization; protochlorophyllide; xanthophyll cycle;
D O I
10.1016/1011-1344(95)07206-3
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
To obtain a clearer understanding of the photosensitization process, we have investigated the effect of photosensitization on the photochemical and non-photochemical energy dissipation in green leaves of wheat (Triticum aestivum L.) and lettuce (Lactuca sativa L.), pretreated with 5-aminolaevulinic acid (ALA) for 2-24 h in the dark, using chlorophyll (Chl) fluorescence quenching analysis and measurement of the influence on CO2 uptake and xanthophyll cycle pigments. In response to dark pretreatment, leaves accumulated high levels of protochlorophyllide (PChlide) and non-metabolized ALA. The dark pretreatment had no effect on the intrinsic photochemical efficiency of photosystem II (PS II). Although quantitative differences exist between wheat and lettuce, exposure to actinic light caused significant effects with a similar overall response pattern in both plant species. Changes in excitation energy dissipation were obtained already by a very low photon flux density of 85 mu mol photons m(-2) s(-1) within a few minutes. CO2 uptake was almost completely suppressed in photosensitized leaves, but they were able to build up the Delta pH necessary to drive de-epoxidation of violaxanthin. Fluorescence quenching analysis revealed that a progressive increase in non-radiative energy dissipation (measured as the non-photochemical quenching of Chl fluorescence, q(N)) was paralleled by a stronger reduction in the primary quinone electron acceptor of PS II (Q(A)) with increasing time of ALA pretreatment in the dark. In the early stages of photosensitization, high-energy state quenching mainly contributed to q(N). In the later stages, q(N) was dominated by a photoinhibitory component together with the photodegradation of xanthophyll cycle pigments, in particular antheraxanthin and zeaxanthin. The latter phenomenon appeared to be promoted in response to a highly increased reduction state of Q(A). If ALA was simultaneously applied to leaves with 4,6-dioxoheptanoic acid, which acts as a competitive inhibitor of the enzyme ALA dehydratase, photosensitization disappeared when PChlide synthesis was completely inhibited, but was enhanced when inhibition was incomplete. Electron paramagnetic resonance studies using the spin trapping technique revealed a specific ALA-mediated formation of hydroxyl and carbon-centred radicals in response to actinic light exposure of chloroplasts. On the basis of these findings, a possible role of ALA is proposed: ALA enhances the photosensitizing effect(s) triggered by PChlide.
引用
收藏
页码:115 / 126
页数:12
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[11]   SUCCINYLACETONE, A POTENT INHIBITOR OF HEME-BIOSYNTHESIS - EFFECT ON CELL-GROWTH, HEME CONTENT AND DELTA-AMINOLEVULINIC-ACID DEHYDRATASE ACTIVITY OF MALIGNANT MURINE ERYTHROLEUKEMIA-CELLS [J].
EBERT, PS ;
HESS, RA ;
FRYKHOLM, BC ;
TSCHUDY, DP .
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 1979, 88 (04) :1382-1390
[12]   UTILIZATION OF AMINOLEVULINIC ACID AS A NITROGEN-SOURCE BY A GREEN-ALGA [J].
ELLIS, R ;
GREENAWALD, M .
PLANT SCIENCE LETTERS, 1985, 37 (03) :213-216
[13]   SPIN TRAPPING OF SUPEROXIDE AND HYDROXYL RADICAL - PRACTICAL ASPECTS [J].
FINKELSTEIN, E ;
ROSEN, GM ;
RAUCKMAN, EJ .
ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS, 1980, 200 (01) :1-16
[14]   THE RELATIONSHIP BETWEEN THE QUANTUM YIELD OF PHOTOSYNTHETIC ELECTRON-TRANSPORT AND QUENCHING OF CHLOROPHYLL FLUORESCENCE [J].
GENTY, B ;
BRIANTAIS, JM ;
BAKER, NR .
BIOCHIMICA ET BIOPHYSICA ACTA, 1989, 990 (01) :87-92
[15]   ADENINE-NUCLEOTIDES AND THE XANTHOPHYLL CYCLE IN LEAVES .2. COMPARISON OF THE EFFECTS OF CO2- AND TEMPERATURE-LIMITED PHOTOSYNTHESIS ON PHOTOSYSTEM-II FLUORESCENCE QUENCHING, THE ADENYLATE ENERGY CHARGE AND VIOLAXANTHIN DE-EPOXIDATION IN COTTON [J].
GILMORE, AM ;
BJORKMAN, O .
PLANTA, 1994, 192 (04) :537-544
[16]   LINEAR-MODELS RELATING XANTHOPHYLLS AND LUMEN ACIDITY TO NONPHOTOCHEMICAL FLUORESCENCE QUENCHING - EVIDENCE THAT ANTHERAXANTHIN EXPLAINS ZEAXANTHIN-INDEPENDENT QUENCHING [J].
GILMORE, AM ;
YAMAMOTO, HY .
PHOTOSYNTHESIS RESEARCH, 1993, 35 (01) :67-78
[17]   DARK INDUCTION OF ZEAXANTHIN-DEPENDENT NONPHOTOCHEMICAL FLUORESCENCE QUENCHING MEDIATED BY ATP [J].
GILMORE, AM ;
YAMAMOTO, HY .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1992, 89 (05) :1899-1903
[18]   LIGHT DEPENDENT DECREASE OF PH-VALUE IN A CHLOROPLAST COMPARTMENT CAUSING ENZYMATIC INTERCONVERSION OF VIOLAXANTHIN TO ZEAXANTHIN - RELATIONS TO PHOTOPHOSPHORYLATION [J].
HAGER, A .
PLANTA, 1969, 89 (03) :224-&
[19]  
HARTEL H, 1993, J PLANT PHYSIOL, V142, P237, DOI 10.1016/S0176-1617(11)80971-5
[20]   RELATIONSHIP BETWEEN QUENCHING OF MAXIMUM AND DARK-LEVEL CHLOROPHYLL FLUORESCENCE IN-VIVO - DEPENDENCE ON PHOTOSYSTEM-II ANTENNA SIZE [J].
HARTEL, H ;
LOKSTEIN, H .
BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1995, 1228 (01) :91-94