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Title: Possible role of interference, protein noise, and sink effects in nonphotochemical quenching in photosynthetic complexes

Here, we analyze theoretically a simple and consistent quantum mechanical model that reveals the possible role of quantum interference, protein noise, and sink effects in the nonphotochemical quenching (NPQ) in light-harvesting complexes (LHCs). The model consists of a network of five interconnected sites (excitonic states of light-sensitive molecules) responsible for the NPQ mechanism. The model also includes the “damaging” and the dissipative channels. The damaging channel is responsible for production of singlet oxygen and other destructive outcomes. In this model, both damaging and “dissipative” charge transfer channels are described by discrete electron energy levels attached to their sinks, that mimic the continuum part of electron energy spectrum. All five excitonic sites interact with the protein environment that is modeled using a stochastic process. Our approach allowed us to derive the exact and closed system of linear ordinary differential equations for the reduced density matrix and its first momentums. Moreover, these equations are solved numerically including for strong interactions between the light-sensitive molecules and protein environment. As an example, we apply our model to demonstrate possible contributions of quantum interference, protein noise, and sink effects in the NPQ mechanism in the CP29 minor LHC. The numerical simulations show that using propermore » combination of quantum interference effects, properties of noise, and sinks, one can significantly suppress the damaging channel. Finally, our findings demonstrate the possible role of interference, protein noise, and sink effects for modeling, engineering, and optimizing the performance of the NPQ processes in both natural and artificial light-harvesting complexes.« less
Authors:
 [1] ;  [2] ;  [3] ;  [1]
  1. Los Alamos National Lab. (LANL) and New Mexican Consortium, Los Alamos, NM (United States)
  2. Univ. of Guadalajara, Jalisco (Mexico)
  3. Weizmann Inst. of Science, Rehovot (Israel)
Publication Date:
OSTI Identifier:
1304705
Report Number(s):
LA-UR--14-29366
Journal ID: ISSN 0303-6812
Grant/Contract Number:
AC52-06NA25396; 15349; 711091
Type:
Accepted Manuscript
Journal Name:
Journal of Mathematical Biology
Additional Journal Information:
Journal Name: Journal of Mathematical Biology; Journal ID: ISSN 0303-6812
Publisher:
Springer
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS Non-Hermitian Hamiltonian; photosynthetic complexes; electron transfer; noise; sink