Folding, assembly, and stability of the major light-harvesting complex of higher plants, LHCII, in the presence of native lipids

TY - JOUR

T1 - Folding, assembly, and stability of the major light-harvesting complex of higher plants, LHCII, in the presence of native lipids

AU - Reinsberg, D

AU - Booth, P J

AU - Jegerschöld, C

AU - Khoo, B J

AU - Paulsen, H

PY - 2000/11/21

Y1 - 2000/11/21

N2 - The influence of thylakoid lipids on the association kinetics and thermal stability of the major light-harvesting complex of photosytem II (LHCII) has been studied in vitro. The apoprotein, light-harvesting chlorophyll a/b-binding protein (Lhcb1), can be refolded and complexed with pigments in detergent solution even in the absence of lipids. Two thylakoid lipids, phosphatidyl glycerol and digalactosyl diacylglycerol, are known to interact specifically with LHCII in vivo. Here we show that both of these lipids, as well as monogalactosyl diacylglycerol, stabilize reconstituted LHCII toward thermal denaturation. Two slow kinetic phases are connected with the establishment of energy transfer between chlorophyll b and chlorophyll a and, thus, are thought to reflect the formation of the pigment-protein complex with tightly coupled chlorophylls. The lipids studied here all have the same effect on the rate of complex assembly in vitro and slow these two kinetic phases by the same degree. Both kinetic phases also slow when reactant concentrations are decreased, suggesting that the corresponding reaction step(s) involve(s) pigment binding.

AB - The influence of thylakoid lipids on the association kinetics and thermal stability of the major light-harvesting complex of photosytem II (LHCII) has been studied in vitro. The apoprotein, light-harvesting chlorophyll a/b-binding protein (Lhcb1), can be refolded and complexed with pigments in detergent solution even in the absence of lipids. Two thylakoid lipids, phosphatidyl glycerol and digalactosyl diacylglycerol, are known to interact specifically with LHCII in vivo. Here we show that both of these lipids, as well as monogalactosyl diacylglycerol, stabilize reconstituted LHCII toward thermal denaturation. Two slow kinetic phases are connected with the establishment of energy transfer between chlorophyll b and chlorophyll a and, thus, are thought to reflect the formation of the pigment-protein complex with tightly coupled chlorophylls. The lipids studied here all have the same effect on the rate of complex assembly in vitro and slow these two kinetic phases by the same degree. Both kinetic phases also slow when reactant concentrations are decreased, suggesting that the corresponding reaction step(s) involve(s) pigment binding.

KW - Carrier Proteins

KW - Chlorophyll

KW - Detergents

KW - Energy Transfer

KW - Galactolipids

KW - Glucosides

KW - Glycolipids

KW - Kinetics

KW - Light-Harvesting Protein Complexes

KW - Lipids

KW - Lutein

KW - Micelles

KW - Phosphatidylglycerols

KW - Photosynthetic Reaction Center Complex Proteins

KW - Photosystem II Protein Complex

KW - Plant Proteins

KW - Protein Folding

KW - Reproducibility of Results

KW - Spectrometry, Fluorescence

KW - Temperature

U2 - 10.1021/bi001365z

DO - 10.1021/bi001365z

M3 - Article

C2 - 11087379

SN - 0006-2960

VL - 39

SP - 14305

EP - 14313

JO - Biochemistry

JF - Biochemistry

IS - 46

ER -