Key points are not available for this paper at this time.
In green plants, the xanthophyll carotenoid zeaxanthin is synthesized transiently under conditions of excess light energy and participates in photoprotection. In the Arabidopsis lut2 npq2 double mutant, all xanthophylls were replaced constitutively by zeaxanthin, the only xanthophyll whose synthesis was not impaired. The relative proportions of the different chlorophyll antenna proteins were strongly affected with respect to the wild-type strain. The major antenna, LHCII, did not form trimers, and its abundance was strongly reduced as was CP26, albeit to a lesser extent. In contrast, CP29, CP24, LHCI proteins, and the PSI and PSII core complexes did not undergo major changes. PSII-LHCII supercomplexes were not detectable while the PSI-LHCI supercomplex remained unaffected. The effect of zeaxanthin accumulation on the stability of the different Lhc proteins was uneven: the LHCII proteins from lut2 npq2 had a lower melting temperature as compared with the wild-type complex while LHCI showed increased resistance to heat denaturation. Consistent with the loss of LHCII, light-state 1 to state 2 transitions were suppressed, the photochemical efficiency in limiting light was reduced and photosynthesis was saturated at higher light intensities in lut2 npq2 leaves, resulting in a photosynthetic phenotype resembling that of high light-acclimated leaves. Zeaxanthin functioned in vivo as a light-harvesting accessory pigment in lut2 npq2 chlorophyll antennae. As a whole, the in vivo data are consistent with the results obtained by using recombinant Lhc proteins reconstituted in vitro with purified zeaxanthin. While PSII photoinhibition was similar in wild type and lut2 npq2 exposed to high light at low temperature, the double mutant was much more resistant to photooxidative stress and lipid peroxidation than the wild type. The latter observation is consistent with an antioxidant and lipid protective role of zeaxanthin in vivo. In green plants, the xanthophyll carotenoid zeaxanthin is synthesized transiently under conditions of excess light energy and participates in photoprotection. In the Arabidopsis lut2 npq2 double mutant, all xanthophylls were replaced constitutively by zeaxanthin, the only xanthophyll whose synthesis was not impaired. The relative proportions of the different chlorophyll antenna proteins were strongly affected with respect to the wild-type strain. The major antenna, LHCII, did not form trimers, and its abundance was strongly reduced as was CP26, albeit to a lesser extent. In contrast, CP29, CP24, LHCI proteins, and the PSI and PSII core complexes did not undergo major changes. PSII-LHCII supercomplexes were not detectable while the PSI-LHCI supercomplex remained unaffected. The effect of zeaxanthin accumulation on the stability of the different Lhc proteins was uneven: the LHCII proteins from lut2 npq2 had a lower melting temperature as compared with the wild-type complex while LHCI showed increased resistance to heat denaturation. Consistent with the loss of LHCII, light-state 1 to state 2 transitions were suppressed, the photochemical efficiency in limiting light was reduced and photosynthesis was saturated at higher light intensities in lut2 npq2 leaves, resulting in a photosynthetic phenotype resembling that of high light-acclimated leaves. Zeaxanthin functioned in vivo as a light-harvesting accessory pigment in lut2 npq2 chlorophyll antennae. As a whole, the in vivo data are consistent with the results obtained by using recombinant Lhc proteins reconstituted in vitro with purified zeaxanthin. While PSII photoinhibition was similar in wild type and lut2 npq2 exposed to high light at low temperature, the double mutant was much more resistant to photooxidative stress and lipid peroxidation than the wild type. The latter observation is consistent with an antioxidant and lipid protective role of zeaxanthin in vivo. When vascular plants or green algae are suddenly exposed to high light, the diepoxide xanthophyll violaxanthin is rapidly converted via the intermediate antheraxanthin to the epoxide-free zeaxanthin under the action of the enzyme violaxanthin deepoxidase (1Yamamoto H.J. Pure Appl. Chem. 1979; 51: 639-648Google Scholar, 2Eskling M. Arvidsson P.-O. Akerlund H.E. Physiol. Plant. 1997; 100: 806-816Google Scholar). The latter enzyme is located in the lumen of the thylakoids and binds to the thylakoid membrane in response to lumen acidification in the light (3Hager A. Holocher K. Planta. 1994; 192: 581-589Google Scholar). Upon return to light limiting conditions, zeaxanthin is epoxidized back to violaxanthin by a zeaxanthin epoxidase enzyme localized on the stromal side of the thylakoid membranes. These stoichiometric and cyclic conversions of violaxanthin, antheraxanthin, and zeaxanthin are called the violaxanthin cycle and have profound effects on light harvesting and light energy utilization in Photosystem (PS) 1The abbreviations used are: PS, photosystem; LHC (I and II), light-harvesting complex (of PSI and PSII); Lhca and Lhcb, protein component of LHCI and LHCII, respectively; CP24, CP26 and CP29, minor LHCII (Lhcb6, Lhcb5, and Lhcb4, respectively); NPQ, nonphotochemical quenching; WT, wild type; TL, thermoluminescence; Φ, quantum yield of O2 evolution; E, Emerson enhancement; DM, dodecyl-d-maltoside. II. It is well established that zeaxanthin synthesis and lumen acidification in high light act synergistically to convert PSII from a state of maximum efficiency of light harvesting to a state of high energy dissipation in the form of heat (4Horton P. Ruban A.V. Walters R.G. Annu. Rev. Plant Physiol. Plant Mol. Biol. 1996; 47: 655-684Google Scholar, 5Demming-Adams B. Adams III, W.W. Nature. 2000; 403: 371-374Google Scholar, 6Müller P. Li X.-P. Niyogi K.K. Plant Physiol. 2001; 125: Scholar). The latter is as a nonphotochemical of chlorophyll is the of the photosynthetic the PSII from its resistance to as in Arabidopsis K.K. Plant Scholar, M. Niyogi K.K. A. Scholar, M. K. Planta. 2001; Scholar). that zeaxanthin the resistance to thylakoid membrane lipid peroxidation by a from NPQ, to M. Niyogi K.K. A. Scholar, M. Niyogi K.K. Plant Physiol. 2000; Scholar, P. M. Niyogi K.K. Plant Physiol. Scholar, Niyogi K.K. Plant Scholar). The xanthophyll cycle and the protective under conditions of light M. K. Planta. 2001; Scholar, Scholar). Zeaxanthin is from green plants under conditions, and transiently only under excess light the of zeaxanthin in the chlorophyll in a of of Arabidopsis an the effects of carotenoid on the and of the photosynthetic M. 1996; Scholar, Plant Physiol. 1997; 639-648Google Scholar, Scholar). In the Arabidopsis zeaxanthin epoxidase is not accumulation of zeaxanthin at the of the antheraxanthin, violaxanthin, and Plant Scholar, A. Scholar). in the mutant, zeaxanthin of the xanthophyll M. 1996; Scholar). xanthophyll had effects on the photosynthetic of the leaves, a stability of the LHCII complexes chlorophyll antenna of and a LHCII and the minor LHCII were M. 1996; Scholar, Plant Physiol. 1997; 639-648Google Scholar, P. P. from to Scholar). the are in the is synthesized from a of the have a of a phenotype and conditions Niyogi K.K. Plant a of is not a is synthesized in that the mutant is not to K.K. Plant Scholar). are reduced to as as xanthophyll are is more than the was with the lut2 mutant, in and the resulting double mutant, not xanthophyll carotenoid zeaxanthin, was its photosynthetic and high light of all xanthophylls by zeaxanthin affected the PSII antenna resulting in a photosynthetic phenotype in that of high light-acclimated leaves, and the of the to photooxidative In to the of proteins the PSII antenna the stability of the Lhca proteins of PSI to by zeaxanthin. Plant and wild type the double mutant lut2 and the mutant of Arabidopsis were under conditions of light of temperature and relative The and were obtained from the Arabidopsis and a of lut2 was from the were exposed to high light of at as M. B. Plant Physiol. Scholar). in were and by as in M. B. Plant Physiol. Scholar). were to that a of the was used in the and was replaced by in the The protein of thylakoid was with a protein using as a The and of thylakoid were with an and a were from thylakoids in a as Scholar). of the were in and of and was the by and Biol. Chem. Scholar). The of the The of the from by a from to were with and a of of with of was The was and was were at under a of of the thylakoid complexes was by Biol. Chem. 2001; Scholar). to of chlorophyll were with and in 1 of by 1 The were at to and by in a and at at The green of the were with a and were to with a as Scholar). The of the proteins was from the of the with The was with of recombinant membrane proteins by in were membranes. were with the CP26 or and were with intensities were using the were by as K. P. Planta. 1996; Scholar). In of Lhca 1 and Lhca proteins were in and reconstituted in vitro with purified as by using a carotenoid from thylakoids or purified zeaxanthin. stability of the minor and major by was by the of the by temperature from to with a of 1 and a of Mol. Biol. 2001; Scholar). The stability of the protein was by the temperature to of the were to an of The was used to the stability of recombinant and from was at and with a as M. B. Plant Physiol. Scholar). The of chlorophyll was with a light at The was a of was in with a light of by a light were with The of the was as a of the antenna of PSII Plant Physiol. Scholar). The quantum yield of PSII was in from the and the was obtained by a of The quantum yield of PSII was in by the is the and is the and the light was by a light from or thylakoid were in with a with light M. Niyogi K.K. Plant Physiol. 2000; Scholar). O2 was from the component of the by with or light at The and the used to the from the have in M. K. Planta. 2001; Scholar, Rev. Plant Physiol. Plant Mol. Biol. 1994; light of was obtained by light an and light of was obtained with an The of the green and light was that the of light by the by the of the was similar in The quantum yield of O2 was by the the of the and the of the Rev. Plant Physiol. Plant Mol. Biol. 1994; Scholar). The Emerson of O2 was in state 1 or in state 2 by a light to the light with a 2 was by the with the light and state 1 was obtained with were with a quantum by 1 was with a M. Plant Scholar). The was at a of from to The of the at was used as an of lipid peroxidation Rev. Plant Physiol. Plant Mol. Biol. 1994; Scholar, M. Plant Scholar). by was at with a O2 were with light by a light was using was in the with a of the Arabidopsis lut2 npq2 double mutant are in the xanthophylls violaxanthin, antheraxanthin, and The xanthophylls are replaced by zeaxanthin, resulting in a and a not different from the wild-type and lut2 npq2 were than wild-type leaves, and was to a of the chlorophyll and carotenoid pigment was by a in the chlorophyll a to to as the lut2 mutant Scholar, Niyogi K.K. A. Scholar). of the chlorophyll is as resulting from a in the PSII light-harvesting binds of the chlorophyll an in the that was to of the chlorophyll a to chlorophyll chlorophyll proteins in the light-harvesting recombinant LHCII complexes reconstituted with zeaxanthin as the only carotenoid have to have an increased chlorophyll as compared with LHCII Biol. Chem. pigment of Arabidopsis and lut2 npq2 are of is the xanthophyll cycle were from plants exposed to a of and were rapidly in pigment not or not or in a PSII and PSI the chlorophyll of wild-type and lut2 npq2 at K. As compared with wild lut2 npq2 a in the PSII and while the PSI was in PSII was in thylakoid The light energy PSI and PSII was in vivo using the 2 the to O2 Rev. Plant Physiol. Plant Mol. Biol. 1994; by an Arabidopsis with a light at a low of The was lower in the double mutant relative to wild a of photosynthetic O2 of its the light is by PSII and O2 are by the to When a light, by is to the light, is and O2 by the photochemical quantum of effect by the Emerson is the of the O2 in the of the light to the O2 in its Rev. Plant Physiol. Plant Mol. Biol. 1994; Scholar). to the light wild-type to the light state 2 by a of light energy the resulting from the of LHCII was low under light conditions In state 1 with was a of light in of was in the double mutant in state 1 in state 2 lower that the double the PSI of and that PSII was limiting in all light the and data a in PSII in lut2 npq2 leaves, to a in the of PSII a of the PSII antenna The in the by lut2 npq2 thylakoid in to the latter PSII and PSI and the antenna of PSII by in vivo chlorophyll in the of the as by Plant Physiol. Scholar). The of the in lut2 npq2 was higher than that in wild type PSII in the effect was by the green in LHCII was in the double loss was with an in the LHCII similar was in the Arabidopsis lut2 mutant Scholar). is that the accumulation of LHCII in lut2 npq2 only the loss of LHCII that the of LHCII in lut2 npq2 was by a of the PSII-LHCII supercomplexes as well as by a loss of the In contrast, the PSI-LHCI was in wild type and lut2 and the PSII was affected by the double was by the of the thylakoid complexes by on the LHCII from the lut2 npq2 while the PSI-LHCI and the PSII were not affected The latter observation is consistent with the of of in lut2 npq2 carotenoid is in the LHCI complexes and the not in the LHCII complexes 2000; Scholar). The different were and protein was by It is that the relative proportions of the PSII were in lut2 and in and in wild type and in lut2 were strongly CP26 in the double mutant while and The abundance of the PSII was by the of the protein and the data are in II. a chlorophyll CP26 was reduced by in lut2 2 was strongly by a of CP24, CP29, and were not Lhca proteins in in a were in lut2 and relative abundance was not with respect to wild of thylakoid complexes of wild-type and lut2 npq2 thylakoids by on of the by protein used to the The and are the and 1 The in are Lhca of the minor and major LHCII in and lut2 npq2 thylakoids were by different of proteins by on or was with chlorophyll and were with protein are of data not not in a was at the of the in and its pigment was by It in that was strongly in in the lut2 npq2 The was and wild type and lut2 These are higher than the in that the in did not from of It is that a of that were in the thylakoid by of the pigment in the of The of in the was are of not not in a The major and minor were by The major LHCII and CP26 were to while and the data of As the in was at protein the and is to the in the major of the PSII that the abundance of was not affected by the double The were to a by not These the in 2 relative to the minor LHCII antenna proteins in lut2 npq2 and that the of the Lhca proteins relative to the PSI was in the were from wild-type and lut2 npq2 The low temperature of the had a major at in with Scholar). the effect on the of the is to LHCII, not from the PSI Scholar). of the LHCII in an in at relative to the The at by was not higher in lut2 npq2 than in wild-type that the in lut2 npq2 were not to O2 was in with the and the of the quantum yield of O2 is in In low light was lower in lut2 npq2 relative to wild type. light a much more in in wild type than in lut2 a more of photosynthesis in the leaves, and is consistent with the antenna of PSII in lut2 npq2 relative to wild-type leaves. at the wild type and lut2 npq2 at high was strongly The results were photosynthetic was by chlorophyll the photochemical efficiency of PSII at low was in the mutant while the quantum yield at high was increased relative to wild type. was at low a of in lut2 npq2 not as lut2 Scholar). O2 was at with a As in the was higher in the double mutant relative to wild that the photosynthetic of lut2 npq2 were not O2 with the or with the and are the quantum yield of relative in green light and in light data are of were in the and at different of light and are of different from the wild type different from the wild O2 different from the wild type different from the wild type different from the wild different from the wild different from the wild type in a of Zeaxanthin in the lut2 npq2 quantum yield of O2 in green light by chlorophyll and carotenoid was compared with the quantum yield in light by only The was similar in wild type and lut2 that the of lut2 npq2 zeaxanthin and are at in to and as accessory that are to energy to the the light of wild-type and lut2 npq2 thylakoid The major the were in the and in the the chlorophyll and the carotenoid in the double as compared with LHCII, recombinant LHCII zeaxanthin a at and the of chlorophyll are at and similar wild type and lut2 npq2 was in the chlorophyll The of the and that zeaxanthin as light-harvesting accessory pigment in lut2 As a that the of zeaxanthin in the thylakoid as of the lut2 npq2 the stability of from lut2 npq2 and wild-type The were the and from wild type and from the double a of LHCII and minor relative to the on the lower melting temperature of minor with respect to major LHCII complex in with Mol. Biol. 2001; Scholar, M. Biol. Chem. Scholar). to in the temperature of the minor and was in lut2 npq2 as compared with wild a stability of Lhc of minor major from and lut2 npq2 thylakoids are of of in a of lut2 were exposed to high light stress at low temperature a that to photosynthetic in wild type and lut2 npq2 a in the PSII photochemical efficiency as by the chlorophyll PSII photoinhibition was similar in wild type and lut2 The of high light and low temperature is the of stress and photoinhibition of wild type and lut2 npq2 Arabidopsis exposed to at was by with a of In lipid peroxidation was in by a M. Plant Scholar). wild-type were to much more to photooxidative than lut2 npq2 leaves. The of the at is to the of lipid in the thylakoid M. Plant Scholar, strongly increased in wild-type in high light remained low in lut2 npq2 in high stress was on of the mutant in chlorophyll and in LHCII Plant Mol. Biol. Scholar, A. Scholar). a of the PSII antenna did not The was the lipid increased rapidly in relative to wild type. The in lut2 npq2 the carotenoid of the PSII antenna complexes is are in proportions on the antenna 2000; Scholar). Arabidopsis with xanthophyll have that the xanthophyll of is M. 1996; Scholar, Plant Physiol. 1997; 639-648Google Scholar, B. M. Plant 1996; Scholar). in vitro of recombinant Lhc proteins with purified have that is to LHCII complexes with xanthophyll zeaxanthin Biol. Chem. Scholar, M. 2001; Scholar). The that in vivo in a xanthophyll mutant all minor and major were in lut2 all were in lut2 npq2 leaves. the relative proportions of the different LHC were strongly that the different not have the to the in xanthophyll The abundance of the major LHCII was resulting a in the PSII antenna in the mutant, and effect was to a loss of and was much affected by the xanthophyll zeaxanthin had effect on the minor LHCII the and the that the of LHCII was strongly by the of zeaxanthin. LHCII and PSII supercomplexes LHCII and the minor was in the double of LHCII was in xanthophyll of Arabidopsis as the M. 1996; Scholar, Plant Physiol. 1997; 639-648Google or the lut2 mutant that the to form is the xanthophyll is In an Arabidopsis the proteins that form LHCII and the of LHCII was by CP26, was trimers, with A.V. M. P. Nature. Scholar). was not the in lut2 the abundance was not affected by the double CP26 was It is LHCII, CP26 was to form similar was in the npq2 mutant of the of the 2 npq2 Arabidopsis mutant Niyogi K.K. A. Plant Physiol. 2001; LHCII and CP26 CP24, CP29, and PSI antenna proteins did The of LHCII was not in CP26 is located at the of the supercomplex Scholar, Ruban A.V. P. and is that loss of LHCII in lut2 npq2 loss of In contrast, and are located in the and the LHCII Scholar, Ruban A.V. P. and to the loss in stability in the double mutant as a the and of the PSII antenna of the lut2 npq2 The of PSII supercomplexes and the of supercomplexes in the thylakoid membrane the quantum efficiency of the of the LHCII and CP26 abundance as well as the loss of LHCII supercomplexes in lut2 npq2 the quantum efficiency of PSII as well as the of the of zeaxanthin in the chlorophyll PSII in a state of energy dissipation of the type zeaxanthin in III, W.W. A. B. Plant Physiol. Scholar). of Zeaxanthin in not LHCII trimers, are the of B. 2000; Scholar). It is that is by the of in form to the thylakoid the is located M. B. Plant Physiol. Scholar). is in to a stability of LHCII in lut2 npq2 resulting a low LHCII The of 2 and in lut2 npq2 relative to wild type that the of LHCII was more affected by the double than the LHCII not to to in the lut2 mutant, is by a loss of LHCII the stability of is not and In contrast, in the mutant, violaxanthin and are replaced by zeaxanthin and the of LHCII in is reduced M. 1996; Scholar, Plant Physiol. 1997; 639-648Google Scholar, Scholar). a different was in the mutant the major effect was in CP26, with the LHCII affected P. P. from to Scholar). and not LHCII was affected in different zeaxanthin to an in the and that the of LHCII M. A. Ruban A.V. A. P. Scholar). The in the of the with the LHCII A. 1996; have to to a of the violaxanthin the of zeaxanthin in the 1997; 51: Scholar). It is to the synthesis of zeaxanthin, not only as a that rapidly light harvesting (4Horton P. Ruban A.V. Walters R.G. Annu. Rev. Plant Physiol. Plant Mol. Biol. 1996; 47: 655-684Google as a that of the PSII antenna to high light conditions by LHCII LHCII stability and LHCII In the xanthophyll cycle as a is by the the photosynthetic of lut2 npq2 and high light-acclimated wild-type leaves. of vascular plants to high light conditions is by a in the major LHCII and an in the photosynthetic R.G. P. Planta. 1994; Scholar). were in lut2 npq2 and in high light was to a in and CP26 while the and were to Walters R.G. P. Planta. 2001; Scholar). of the PSII antenna proteins was in lut2 npq2 wild type. of the photosynthetic of lut2 npq2 of high light Arabidopsis plants, the that zeaxanthin is in the of the PSII antenna to the light is by with with the mutant at low and light intensities have that the and are more in mutant as compared with wild type not in with In of in complexes reconstituted in vitro are similar to wild type LHCII with respect to energy and Mol. Biol. 2001; Scholar). In major of the as antenna was in compared with wild-type LHCII Scholar). is in vivo by on and by of The high photochemical of lut2 npq2 in green light and the the and showed that zeaxanthin functioned as a light-harvesting accessory pigment that was to energy to the that zeaxanthin was to antenna proteins and that zeaxanthin was as in the membrane lipid the lut2 npq2 LHCII were to than wild-type LHCII and is consistent with in vitro of the stability of reconstituted with zeaxanthin Mol. Biol. 2001; Scholar). In to the antenna of PSI was not affected by the lut2 npq2 double that the stability of the was not by zeaxanthin. have the stability of recombinant LHCI proteins and in vitro with zeaxanthin or violaxanthin, and have compared the with of LHCI complexes in Scholar, Biol. Chem. Scholar). As in zeaxanthin increased the of and was not violaxanthin was in vitro and in vivo that the PSI antenna is to the of all xanthophylls by zeaxanthin and that and Lhca proteins of violaxanthin zeaxanthin, is consistent with the that LHCI violaxanthin with zeaxanthin in vivo and in vitro with high efficiency Biol. Chem. stability of recombinant LHCI proteins with different carotenoid of Biol. Chem. in a lut2 npq2 to vitro have that LHCII reconstituted with zeaxanthin is as to as wild-type LHCII Mol. Biol. 2001; Scholar). The of PSII was in vivo in When exposed to excess light energy by the of high light and low temperature, the of PSII as by the was similar in wild-type and mutant was with a of by photooxidative of thylakoid as with a of lipid peroxidation lipid peroxidation much more rapidly in wild type than in lut2 a strongly increased of the double mutant to The of the double mutant by its photosynthetic in high light at low temperature was similar in wild-type and lut2 npq2 and energy dissipation via the is in lut2 npq2 as is in the lut2 mutant Scholar, Niyogi K.K. A. Scholar). is that the high of the mutant to the of the PSII antenna In with green algae Appl. Scholar, A. Planta. antenna not vascular plants from A. Plant Physiol. Scholar, 1994; Scholar). a chlorophyll mutant was not more to high light stress than wild-type M. Plant Physiol. 1997; Scholar). As in to was not in the chlorophyll Arabidopsis mutant that is in LHCII the high of lut2 npq2 is to the of high of zeaxanthin in the of Arabidopsis have its role in the used by plants to excess light energy (4Horton P. Ruban A.V. Walters R.G. Annu. Rev. Plant Physiol. Plant Mol. Biol. 1996; 47: 655-684Google Scholar, 6Müller P. Li X.-P. Niyogi K.K. Plant Physiol. 2001; 125: zeaxanthin of membrane lipid peroxidation M. Niyogi K.K. A. Scholar, M. K. Planta. 2001; Scholar). was by P. M. Niyogi K.K. Plant Physiol. showed that zeaxanthin the of an Arabidopsis mutant to photooxidative plants the enzyme high of zeaxanthin and an increased to photooxidative stress P. Nature. Scholar, Plant Mol. Biol. Scholar). that a mutant is to photooxidative stress is consistent with the antioxidant and lipid of zeaxanthin. It is not zeaxanthin synthesized the of the xanthophyll cycle O2 and lipid peroxidation as in the lipid or to are data that are with a zeaxanthin and thylakoid membrane M. K. Planta. 2001; Scholar, Niyogi K.K. Plant Scholar, M. B. Plant Physiol. Scholar). zeaxanthin is located in the light-harvesting of lut2 npq2 and is to and a of zeaxanthin to as in the lipid the pigment in the of lut2 npq2 was in zeaxanthin, with a of The latter is much higher than the the zeaxanthin were from LHC denaturation. have and the major LHCII or in lut2 npq2 or wild to the that zeaxanthin to the Biol. Chem. Scholar). the of zeaxanthin from of zeaxanthin CP26, CP29, CP24, and LHCII in relative yield a of and a zeaxanthin of while to of zeaxanthin in of lut2 npq2 as in vivo. wild type a lower of the of in the and the of in the in lut2 npq2 are of In wild the of is much These of in the of zeaxanthin from a with low the carotenoid in the in the membrane lipid and to the protein in with the in the lipid a that of zeaxanthin photooxidative stress in green algae Niyogi K.K. Plant Scholar). The zeaxanthin in lut2 npq2 thylakoid by different by as a lipid peroxidation A. K. K. or by with P. Scholar). have to the antioxidant of zeaxanthin under conditions the of the xanthophyll in the protein the lipid or The of violaxanthin to zeaxanthin is in the of the thylakoid M. Niyogi K.K. A. that the of high of zeaxanthin in the lut2 npq2 mutant increased the thylakoid to photooxidative the photosynthetic of Arabidopsis was not affected by the of all xanthophylls by zeaxanthin, that the of the is a reduced to low light lut2 npq2 had a antenna that was to state had a reduced photochemical efficiency in low light and an photosynthetic in high These photosynthetic are to a and of the major
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