Origin and properties of fluorescence emission from the extrinsic 33 kDa manganese stabilizing protein of higher plant water oxidizing complex

T. Shutova, G. Deikus, K. D. Irrgang, V. V. Klimov, G. Renger

Research output: Contribution to journalArticlepeer-review

29 Scopus citations

Abstract

The fluorescence properties of the isolated extrinsic 33 kDa subunit acting as 'manganese stabilizing protein' (MSP) of the water oxidizing complex in photosynthesis was analyzed in buffer solution. Measurements of the emission spectra as a function of excitation wavelength, pH and temperature led to the following results: (a) under all experimental conditions the spectra monitored were found to be the composite of two contributions referred to as '306 nm band' and 'long-wavelength band', (b) the excitation spectra of these two bands closely resemble those of tyrosine and tryptophan in solution, respectively, (c) the spectral shape of the '306 nm band' is virtually independent on pH but its amplitude drastically decreases in the alkaline with a pK of 11.7, (d) the amplitude of the 'long-wavelength' emission band at alkaline pH slightly increases when the pH rises from 7.2 to about 11.3 followed by a sharp decline at higher pH, and (e) the shape of the overall spectrum at pH 7.2 is only slightly changed upon heating to 90°C whereas the amplitude significantly declines. Based on these findings the two distinct fluorescence bands are ascribed to tyrosine(s) ('306 nm band') and the only tryptophan residue W241 of MSP from higher plants ('long-wavelength band') as emitters which are both embedded into a rather hydrophobic environment.

Original languageEnglish
Pages (from-to)371-378
Number of pages8
JournalBiochimica et Biophysica Acta - Bioenergetics
Volume1504
Issue number2-3
DOIs
StatePublished - 2 Apr 2001
Externally publishedYes

Keywords

  • Fluorescence
  • Manganese stabilizing protein
  • Photosystem II
  • pH dependence

Fingerprint

Dive into the research topics of 'Origin and properties of fluorescence emission from the extrinsic 33 kDa manganese stabilizing protein of higher plant water oxidizing complex'. Together they form a unique fingerprint.

Cite this