title: Rerouting excitation transfers in the Fenna-Matthews-Olson complex.
abstract: We investigate, using the hierarchy method, the entanglement and the excitation transfer efficiency of the Fenna-Matthews-Olson (FMO) complex under two different local modifications: the suppression of transitions between particular sites and localized changes to the protein environment. We find that inhibiting the connection between site 5 and site 6, or completely disconnecting site 5 from the complex, leads to a dramatic enhancement of the entanglement between site 6 and site 7. Similarly, the transfer efficiency actually increases if site 5 is entirely disconnected from the complex. We further show that if sites 5 and 7 are conjointly removed, the efficiency falls. This suggests that while not contributing to the transport efficiency in a normal complex, site 5 may introduce a redundant transport route in case of damage to site 7. Our results suggest an overall robustness of the excitation-energy transfer in the FMO complex under mutations, local defects, and other abnormal situations.
authors.affiliation: Department of Physics and National Center for Theoretical Sciences, National Cheng-Kung University, Tainan 701, Taiwan and CEMS, RIKEN, Saitama, 351-0198, Japan.
authors.forename: Guang-Yin
authors.initials: GY
authors.lastname: Chen
authors.forename: Neill
authors.initials: N
authors.lastname: Lambert
authors.forename: Che-Ming
authors.initials: CM
authors.lastname: Li
authors.forename: Yueh-Nan
authors.initials: YN
authors.lastname: Chen
authors.forename: Franco
authors.initials: F
authors.lastname: Nori