Immobilization of light-harvesting chlorophyll a/b complex (LHCIIb) studied by surface plasmon field-enhanced fluorescence spectroscopy

Langmuir. 2008 Sep 2;24(17):9661-7. doi: 10.1021/la801143e. Epub 2008 Jul 30.

Abstract

The major light-harvesting chlorophyll a/ b complex (LHCIIb) of the photosynthetic apparatus in green plants can be viewed as a protein scaffold binding and positioning a large number of pigment molecules that engage in rapid excitation energy transfer. This property makes LHCIIb potentially interesting as a light harvester (or a model thereof) in photoelectronic applications. Such applications would require the immobilization of LHCIIb (or similar dye-protein complexes) on a solid surface. In this work, the immobilization of recombinant LHCIIb is tested and optimized on functionalized gold surfaces via a histidine 6 tag (His tag) in the protein moiety. Immobilization efficiency and kinetics are analyzed by using surface plasmon resonance (SPR) and surface plasmon field-enhanced fluorescence spectroscopy (SPFS). The latter was also used to assess the integrity of immobilized LHCIIb by recording Chl b-sensitized Chl a emission spectra. Since His tags have been included in a substantial number of recombinant proteins, the immobilization technique developed here for LHCIIb presumably can be extended to a large range of other membrane and water-soluble proteins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biotinylation
  • Chlorophyll / chemistry*
  • Chlorophyll A
  • Gold
  • Histidine / chemistry
  • Kinetics
  • Light
  • Models, Chemical
  • Molecular Conformation
  • Photochemistry / methods
  • Photosystem II Protein Complex / chemistry*
  • Spectrometry, Fluorescence / methods*
  • Streptavidin / chemistry
  • Surface Plasmon Resonance / methods*
  • Time Factors

Substances

  • Photosystem II Protein Complex
  • Chlorophyll
  • Histidine
  • chlorophyll b
  • Gold
  • Streptavidin
  • Chlorophyll A