Molecular Mechanisms of Nonphotochemical Quenching in the LHCSR3 Protein of Chlamydomonas reinhardtii.

ABSTRACT: Photosynthetic organisms possess photoprotection mechanisms from excess light conditions. The fastest response consists in the pH-triggered activation of a dissipation channel of the energy absorbed by the chlorophylls into heat, called nonphotochemical quenching. In green algae, the pigment binding complex LHCSR3 acts both as a chlorophyll quencher and as a pH detector. In this work, we study the quenching of the LHCSR3 protein in vitro considering two different protein aggregation states and two pH conditions using a combination of picosecond time-resolved photoluminescence and femtosecond transient absorption in the visible and NIR spectral regions. We find that the mechanisms at the basis of LHCSR3 quenching activity are always active, even at pH 7.5 and low aggregation. However, quenc

SUBMITTER: de la Cruz Valbuena G 

PROVIDER: S-EPMC6613783 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature