EurekaMag
+ Most Popular
Cunninghamia lanceolata plantations in China
Mammalian lairs in paleo ecological studies and palynology
Studies on technological possibilities in utilization of anhydrous milk fat for production of recombined butter-like products
Should right-sided fibroelastomas be operated upon?
Large esophageal lipoma
Apoptosis in the mammalian thymus during normal histogenesis and under various in vitro and in vivo experimental conditions
Poissons characoides nouveaux ou non signales de l'Ilha do Bananal, Bresil
Desensitizing efficacy of Colgate Sensitive Maximum Strength and Fresh Mint Sensodyne dentifrices
Administration of fluid by subcutaneous infusion: revival of a forgotten method
Tundra mosquito control - an impossible dream?
Schizophrenia for primary care providers: how to contribute to the care of a vulnerable patient population
Geochemical pattern analysis; method of describing the Southeastern limestone regional aquifer system
Incidence of low birth weights in a hospital of Mexico City
Tabanidae
Graded management intensity of grassland systems for enhancing floristic diversity
Microbiology and biochemistry of cheese and fermented milk
The ember tetra: a new pygmy characid tetra from the Rio das Mortes, Brazil, Hyphessobrycon amandae sp. n. (Pisces, Characoidei)
Risk factors of contrast-induced nephropathy in patients after coronary artery intervention
Renovation of onsite domestic wastewater in a poorly drained soil
Observations of the propagation velocity and formation mechanism of burst fractures caused by gunshot
Systolic blood pressure in a population of infants in the first year of life: the Brompton study
Haematological studies in rats fed with metanil yellow
Studies on pasteurellosis. I. A new species of Pasteurella encountered in chronic fowl cholera
Dormancy breaking and germination of Acacia salicina Lindl. seeds
therapy of lupus nephritis. a two-year prospective study

Photosystem II chlorophyll a fluorescence lifetimes and intensity are independent of the antenna size differences barley wild-type and chlorina mutants: Photochemical quenching and xanthophyll cycle-dependent nonphotochemical quenching of fluorescence


Photosystem II chlorophyll a fluorescence lifetimes and intensity are independent of the antenna size differences barley wild-type and chlorina mutants: Photochemical quenching and xanthophyll cycle-dependent nonphotochemical quenching of fluorescence



Photosynthesis Research 48(1-2): 171-187



ISSN/ISBN: 0166-8595

Photosystem II (PS II) chlorophyll (Chl) a fluorescence lifetimes were measured in thylakoids and leaves of barley wild-type and chlorina f104 and f2 mutants to determine the effects of the PS II Chl a+b antenna size on the deexcitation of absorbed light energy. These barley chlorina mutants have drastically reduced levels of PS II light-harvesting Chls and pigment-proteins when compared to wild-type plants. However, the mutant and wild type PS II Chl a fluorescence lifetimes and intensity parameters were remarkably similar and thus independent of the PS II light-harvesting antenna size for both maximal (at minimum Chi fluorescence level, F-o) and minimal rates of PS II photochemistry (at maximum Chl fluorescence level, F-m). Further, the fluorescence lifetimes and intensity parameters, as affected by the trans-thylakoid membrane pH gradient (DELTA-pH) and the carotenoid pigments of the xanthophyll cycle, were also similar and independent of the antenna size differences. In the presence of a DELTA-pH, the xanthophyll cycle-dependent processes increased the fractional intensity of a Chl a fluorescence lifetime distribution centered around 0.4-0.5 ns, at the expense of a 1.6 ns lifetime distribution (see Gilmore et al. (1995) Proc Natl Acad Sci USA 92: 2273-2277). When the zeaxanthin and antheraxanthin concentrations were measured relative to the number of PS II reaction center units, the ratios of fluorescence quenching to (xanthophyll) were similar between the wild-type and chlorina f 104. However, the chlorina f 104, compared to the wild-type, required around 2.5 times higher concentrations of these xanthophylls relative to Chl a+b to obtain the same levels of xanthophyll cycle-dependent fluorescence quenching. We thus suggest that, at a constant DELTA-pH, the fraction of the short lifetime distribution is determined by the concentration and thus binding frequency of the xanthophylls in the PS II inner antenna. The DELTA-pH also affected both the widths and centers of the lifetime distributions independent of the xanthophyll cycle. We suggest that the combined effects of the xanthophyll cycle and DELTA-pH cause major conformational changes in the pigment-protein complexes of the PS II inner or core antennae that switch a normal PS II unit to an increased rate constant of heat dissipation. We discuss a model of the PS II photochemical apparatus where PS II photochemistry and xanthophyll cycle-dependent energy dissipation are independent of the Peripheral antenna size.

Please choose payment method:






(PDF emailed within 1 workday: $29.90)

Accession: 009192186

Download citation: RISBibTeXText

Related references

Photosystem II chlorophyll a fluorescence lifetimes and intensity are independent of the antenna size differences between barley wild-type and chlorina mutants: photochemical quenching and xanthophyll cycle-dependent nonphotochemical quenching of fluorescence. Photosynthesis Research 48(1-2): 171-187, 1996

Xanthophyll biosynthetic mutants of Arabidopsis thaliana: altered nonphotochemical quenching of chlorophyll fluorescence is due to changes in Photosystem II antenna size and stability. Biochimica et Biophysica Acta 1553(3): 309-319, 2002

Kinetic Studies on the Xanthophyll Cycle in Barley Leaves (Influence of Antenna Size and Relations to Nonphotochemical Chlorophyll Fluorescence Quenching). Plant Physiology 110(2): 471-482, 1996

Xanthophyll cycle-dependent quenching of photosystem Ii chlorophyll a fluorescence: formation of a quenching complex with a short fluorescence lifetime. Proceedings of the National Academy of Sciences of the United States of America 92(6): 2273-2277, 1995

Relationship between antenna size, xanthophyll-cycle activity and non-photochemical fluorescence quenching in barley leaves. Photochemistry and Photobiology 63(SPEC ISSUE): 34S, 1996

Kinetic studies on the xanthophyll cycle in barley leaves : influence of antenna size and relations to nonphotochemica chlorophyll fluorescence quenching. Plant Physiology (Bethesda) 110(2): 471-482, 1996

Nonphotochemical quenching of chlorophyll fluorescence in leaves: influence of photosystem II antenna size and violaxanthin de-epoxidation. Photosynthesis: from light to biosphere: Volume I Proceedings of the Xth International Photosynthesis Congress, Montpellier, France, 20-25 August 1995: 291-294, 1995

Xanthophyll cycle dependent non-photochemical quenching of chlorophyll a fluorescence at low physiological temperatures. Photosynthesis: from light to biosphere Volume IV Proceedings of the Xth International Photosynthesis Congress, Montpellier, France, 20-25 August 1995: 825-828, 1995

Non-photochemical quenching of chlorophyll a fluorescence: early history and characterization of two xanthophyll-cycle mutants of Chlamydomonas reinhardtii. Functional Plant Biology: Fpb 29(10): 1141-1155, 2002

Non-photochemical quenching of chlorophyll a fluorescence: Early history and characterization of two xanthophyll-cycle mutants of Chlamydomonas reinhardtii. Functional Plant Biology 29(10): 1141-1155, 2002

Xanthophyll biosynthetic mutants of Arabidopsis thaliana Mechanistic and molecular basis for altered nonphotochemical quenching of chlorophyll fluorescence. Plant Biology (Rockville) : 21, 2001

The origins of nonphotochemical quenching of chlorophyll fluorescence in photosynthesis. Direct quenching by P680+ in photosystem Ii enriched membranes at low pH. Biochemistry 36(4): 749-755, 1997

Dynamics of Xanthophyll-Cycle Activity in Different Antenna Subcomplexes in the Photosynthetic Membranes of Higher Plants (The Relationship between Zeaxanthin Conversion and Nonphotochemical Fluorescence Quenching). Plant Physiology 115(4): 1609-1618, 1997

Dynamics of xanthophyll-cycle activity in different antenna subcomplexes in the photosynthetic membranes of higher plants : The relationship between zeaxanthin conversion and nonphotochemical fluorescence quenching. Plant Physiology (Bethesda) 115(4): 1609-1618, 1997

Xanthophyll cycle-dependent nonphotochemical quenching in Photosystem II: mechanistic insights gained from Arabidopsis thaliana L. mutants that lack violaxanthin deepoxidase activity and. Photosynthesis research 7(1-2): 89-101, 2001