Thermo-optically induced reorganizations in the main light harvesting antenna of plants. II

Indications for the role of LHCII-only macrodomains in thylakoids

Jens Kai Holm, Zsuzsanna Varkonyi, Laszlo Kovacs, Dorthe Posselt, Gyozo Garab

    Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

    Resumé

    We have investigated the circular dichroism spectral transients associated with the light-induced reversible reorganizations in chirally organized macrodomains of pea thylakoid membranes and loosely stacked lamellar aggregates of the main chlorophyll a/b light harvesting complexes (LHCII) isolated from the same membranes. These reorganizations have earlier been assigned to originate from a thermo-optic effect. According to the thermo-optic mechanism, fast local thermal transients due to dissipation of the excess excitation energy induce elementary structural changes in the close vicinity of the dissipation [Cseh et al. (2000) Biochemistry 39: 15250–15257]. Here we show that despite the markedly different CD spectra in the dark, the transient (light-minus-dark) CD spectra associated with the structural changes induced by high light in thylakoids and LHCII are virtually indistinguishable. This, together with other close similarities between the two systems, strongly suggests that the gross short-term, thermo-optically induced structural reorganizations in the membranes occur mainly, albeit probably not exclusively, in the LHCII-only domains [Boekema et al. (2000) J Mol Biol 301: 1123–1133]. Hence, LHCII-only domains might play an important role in light adaptation and photoprotection of plants.
    OriginalsprogEngelsk
    TidsskriftPhotosynthesis Research
    Vol/bind86
    Sider (fra-til)275-282
    ISSN0166-8595
    StatusUdgivet - 2005

    Citer dette

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    title = "Thermo-optically induced reorganizations in the main light harvesting antenna of plants. II: Indications for the role of LHCII-only macrodomains in thylakoids",
    abstract = "We have investigated the circular dichroism spectral transients associated with the light-induced reversible reorganizations in chirally organized macrodomains of pea thylakoid membranes and loosely stacked lamellar aggregates of the main chlorophyll a/b light harvesting complexes (LHCII) isolated from the same membranes. These reorganizations have earlier been assigned to originate from a thermo-optic effect. According to the thermo-optic mechanism, fast local thermal transients due to dissipation of the excess excitation energy induce elementary structural changes in the close vicinity of the dissipation [Cseh et al. (2000) Biochemistry 39: 15250–15257]. Here we show that despite the markedly different CD spectra in the dark, the transient (light-minus-dark) CD spectra associated with the structural changes induced by high light in thylakoids and LHCII are virtually indistinguishable. This, together with other close similarities between the two systems, strongly suggests that the gross short-term, thermo-optically induced structural reorganizations in the membranes occur mainly, albeit probably not exclusively, in the LHCII-only domains [Boekema et al. (2000) J Mol Biol 301: 1123–1133]. Hence, LHCII-only domains might play an important role in light adaptation and photoprotection of plants.",
    author = "Holm, {Jens Kai} and Zsuzsanna Varkonyi and Laszlo Kovacs and Dorthe Posselt and Gyozo Garab",
    year = "2005",
    language = "English",
    volume = "86",
    pages = "275--282",
    journal = "Photosynthesis Research",
    issn = "0166-8595",
    publisher = "Springer Netherlands",

    }

    Thermo-optically induced reorganizations in the main light harvesting antenna of plants. II : Indications for the role of LHCII-only macrodomains in thylakoids. / Holm, Jens Kai; Varkonyi, Zsuzsanna; Kovacs, Laszlo; Posselt, Dorthe; Garab, Gyozo.

    I: Photosynthesis Research, Bind 86, 2005, s. 275-282.

    Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

    TY - JOUR

    T1 - Thermo-optically induced reorganizations in the main light harvesting antenna of plants. II

    T2 - Indications for the role of LHCII-only macrodomains in thylakoids

    AU - Holm, Jens Kai

    AU - Varkonyi, Zsuzsanna

    AU - Kovacs, Laszlo

    AU - Posselt, Dorthe

    AU - Garab, Gyozo

    PY - 2005

    Y1 - 2005

    N2 - We have investigated the circular dichroism spectral transients associated with the light-induced reversible reorganizations in chirally organized macrodomains of pea thylakoid membranes and loosely stacked lamellar aggregates of the main chlorophyll a/b light harvesting complexes (LHCII) isolated from the same membranes. These reorganizations have earlier been assigned to originate from a thermo-optic effect. According to the thermo-optic mechanism, fast local thermal transients due to dissipation of the excess excitation energy induce elementary structural changes in the close vicinity of the dissipation [Cseh et al. (2000) Biochemistry 39: 15250–15257]. Here we show that despite the markedly different CD spectra in the dark, the transient (light-minus-dark) CD spectra associated with the structural changes induced by high light in thylakoids and LHCII are virtually indistinguishable. This, together with other close similarities between the two systems, strongly suggests that the gross short-term, thermo-optically induced structural reorganizations in the membranes occur mainly, albeit probably not exclusively, in the LHCII-only domains [Boekema et al. (2000) J Mol Biol 301: 1123–1133]. Hence, LHCII-only domains might play an important role in light adaptation and photoprotection of plants.

    AB - We have investigated the circular dichroism spectral transients associated with the light-induced reversible reorganizations in chirally organized macrodomains of pea thylakoid membranes and loosely stacked lamellar aggregates of the main chlorophyll a/b light harvesting complexes (LHCII) isolated from the same membranes. These reorganizations have earlier been assigned to originate from a thermo-optic effect. According to the thermo-optic mechanism, fast local thermal transients due to dissipation of the excess excitation energy induce elementary structural changes in the close vicinity of the dissipation [Cseh et al. (2000) Biochemistry 39: 15250–15257]. Here we show that despite the markedly different CD spectra in the dark, the transient (light-minus-dark) CD spectra associated with the structural changes induced by high light in thylakoids and LHCII are virtually indistinguishable. This, together with other close similarities between the two systems, strongly suggests that the gross short-term, thermo-optically induced structural reorganizations in the membranes occur mainly, albeit probably not exclusively, in the LHCII-only domains [Boekema et al. (2000) J Mol Biol 301: 1123–1133]. Hence, LHCII-only domains might play an important role in light adaptation and photoprotection of plants.

    M3 - Journal article

    VL - 86

    SP - 275

    EP - 282

    JO - Photosynthesis Research

    JF - Photosynthesis Research

    SN - 0166-8595

    ER -