Possible photoacoustic detection of cyclic electron transport around Photosystem II in photoinhibited thylakoid preparations

Line Lapointe, Norman P.A. Huner, Roger M. Leblanc, Robert Carpentier

Research output: Contribution to journalArticle

11 Scopus citations

Abstract

This study was undertaken to compare the kinetics of chlorophyll a fluorescence, of Photosystem II and Photosystem I electron transport activity, of the number of atrazine-binding sites, and of the photoacoustic signal during photoinhibition of rye (Secale cereale L.) thylakoids. Once all Photosystem II activity and all chlorophyll a variable fluorescence (Fv) were lost, a substantial amount of energy was still stored in thylakoid membranes, suggesting photosynthetic activity. A significant fraction of atrazine-binding sites remained functional. Both the number of atrazine-binding sites and the amount of energy stored in the thylakoids showed a slow decrease once all Photosystcm II activity was lost. The remaining energy storage is suggested to measure photosynthetic activity in Photosystem II β centres, once all Photosystem II α centres are inactivated. These Photosystem II β centres could store energy via a cyclic electron pathway involving cytochrome b-559.

Original languageEnglish (US)
Pages (from-to)43-48
Number of pages6
JournalBBA - Bioenergetics
Volume1142
Issue number1-2
DOIs
StatePublished - Apr 5 1993
Externally publishedYes

Keywords

  • Cyclic electron transport
  • Photoacoustic spectroscopy
  • Photoinhibition
  • Photosystem II
  • Thylakoid, isolated

ASJC Scopus subject areas

  • Biophysics

Fingerprint Dive into the research topics of 'Possible photoacoustic detection of cyclic electron transport around Photosystem II in photoinhibited thylakoid preparations'. Together they form a unique fingerprint.

  • Cite this