Hg2+ reacts with different components of the NADPH:: Protochlorophyllide oxidoreductase macrodomains

被引:25
作者
Solymosi, K
Lenti, K
Mysliwa-Kurdziel, B
Fidy, J
Strzalka, K
Böddi, B
机构
[1] Eotvos Lorand Univ, Dept Plant Anat, H-1117 Budapest, Hungary
[2] Jagiellonian Univ, Dept Plant Physiol & Biochem, Krakow, Poland
[3] Semmelweis Univ, Dept Biophys & Radiat Biol, Bucharest, Romania
[4] Hungarian Acad Sci, MTS SE Res Grp Biophys, Budapest, Hungary
关键词
mercury; Hg2+; protochlorophyllide; NADPH; protopheophorbide; Shibata shift; activity loss;
D O I
10.1055/s-2004-817893
中图分类号
Q94 [植物学];
学科分类号
071001 ;
摘要
The molecular background of Hg2+-induced inhibition of protochlorophyllide (Pchlide) photoreduction was investigated in homogenates of dark-grown wheat leaves. Our earlier work showed that 15 min incubation with 10(-2) M Hg2+ completely inhibits the activity of NADPH: Pchlide oxidoreductase (Lenti et al., 2002). Detailed analysis of spectra recorded at 10 K indicated the appearance of emission bands at 638 and 650 nm, which are characteristic for NADP(+)-Pchlide complexes. Fluorescence emission spectra recorded with different excitation wavelengths, fluorescence lifetime measurements and the analysis of acetone extractions revealed that Hg2+ can also react directly with Pchlide, resulting in protopheophorbide formation. At 10(-3) M Hg2+, the phototransformation was complete but the blue shift of the chlorophyllide emission band speeded up remarkably. This indicates oxidation of the NADPH molecules that have a structural role in keeping together the etioplast inner membrane components. We suggest a complex model for the Hg2+ effect: depending on concentration it can react with any components of the NADPH:Pchlide oxidoreductase macrodomains.
引用
收藏
页码:358 / 367
页数:10
相关论文
共 68 条
[31]   Determination of trace lead, cadmium and mercury by on-line column enrichment followed by RP-HPLC as metal-tetra-(4-bromophenyl)-porphyrin chelates [J].
Hu, QF ;
Yang, GY ;
Yin, JY ;
Yao, Y .
TALANTA, 2002, 57 (04) :751-756
[32]   Protochlorophyllide forms and energy transfer in dark-grown wheat leaves.: Studies by conventional and laser excited fluorescence spectroscopy between 10 K-100K [J].
Kis-Petik, K ;
Böddi, B ;
Kaposi, AD ;
Fidy, J .
PHOTOSYNTHESIS RESEARCH, 1999, 60 (01) :87-98
[33]   CORRELATED APPEARANCE OF PROLAMELLAR BODIES, PROTOCHLOROPHYLL(IDE) SPECIES, AND SHIBATA SHIFT DURING DEVELOPMENT OF BEAN ETIOPLASTS IN DARK [J].
KLEIN, S ;
SCHIFF, JA .
PLANT PHYSIOLOGY, 1972, 49 (04) :619-&
[34]   Environmental relevance of heavy metal-substituted chlorophylls using the example of water plants [J].
Kupper, H ;
Küpper, FC ;
Spiller, M .
JOURNAL OF EXPERIMENTAL BOTANY, 1996, 47 (295) :259-266
[35]   Heavy metal-induced inhibition of photosynthesis:: Targets of in vivo heavy metal chlorophyll formation [J].
Küpper, H ;
Setlík, I ;
Spiller, M ;
Küpper, FC ;
Prásil, O .
JOURNAL OF PHYCOLOGY, 2002, 38 (03) :429-441
[36]   In situ detection of heavy metal substituted chlorophylls in water plants [J].
Küpper, H ;
Küpper, FC ;
Spiller, M .
PHOTOSYNTHESIS RESEARCH, 1998, 58 (02) :123-133
[37]   ANALYSIS OF FLUORESCENCE DECAY KINETICS FROM VARIABLE-FREQUENCY PHASE-SHIFT AND MODULATION DATA [J].
LAKOWICZ, JR ;
LACZKO, G ;
CHEREK, H ;
GRATTON, E ;
LIMKEMAN, M .
BIOPHYSICAL JOURNAL, 1984, 46 (04) :463-477
[38]   INORGANIC MERCURY(II)-BINDING COMPONENTS IN NORMAL HUMAN-BLOOD SERUM [J].
LAU, S ;
SARKAR, B .
JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH, 1979, 5 (05) :907-916
[39]   Protochlorophyllide photoreduction [J].
Lebedev, N ;
Timko, MP .
PHOTOSYNTHESIS RESEARCH, 1998, 58 (01) :5-23
[40]   Mercury inhibits the activity of the NADPH:protochlorophyllide oxidoreductase (POR) [J].
Lenti, K ;
Fodor, F ;
Böddi, B .
PHOTOSYNTHETICA, 2002, 40 (01) :145-151