Cryo‐electron microscopy structure of the intact photosynthetic light‐harvesting antenna‐reaction center complex from a green sulfur bacterium

Abstract

The photosynthetic reaction center complex (RCC) of green sulfur bacteria (GSB) consists of the membrane-imbedded RC core and the peripheric energy transmitting proteins called Fenna-Matthews-Olson (FMO). Functionally, FMO transfers the absorbed energy from a huge peripheral light-harvesting antenna named chlorosome to the RC core where charge separation occurs. In vivo, one RC was found to bind two FMOs, however, the intact structure of RCC as well as the energy transfer mechanism within RCC remain to be clarified. Here we report a

Structure of the Acidobacteria homodimeric reaction center bound with cytochrome c

“…6a), which was more similar to the distribution of the lowmolecular-weight proteins in PSII 20 (Supplementary Fig. 6e) than to the distribution of surrounding subunits in the HbRC 6 , GsbRC 21,22 and PSI 10 (Supplementary Fig. 6b-d).…”

Single-atom nanozymes as promising catalysts for biosensing and biomedical applications

“…In vivo imaging and spectroscopy analysis will be a key to unravelling the mechanistic details, which can be aided by low-temperature electron microscopy measurements. 209,210…”

“…In vivo imaging and spectroscopy analysis will be a key to unravelling the mechanistic details, which can be aided by low-temperature electron microscopy measurements. 209,210 Author contributions Xueqian Xiao: investigation, writingoriginal draft; Xiao Hu: investigation, writingoriginal draft; Qiming Liu: writingreview & editing; Yulin Zhang: writingoriginal draft; Guo-Jun Zhang: resources, writingoriginal draft; Shaowei Chen: conceptualization, resources, writingreview & editing.…”

Incoherent Energy Transfer between the Baseplate and FMO Protein Explored at Ideal Geometries

“…This would allow for more flexibility of the overall conformation between CBP, FMO, and RC. With the FMO–RC binding mode known, , a full model of these systems is now possible; the CBP may even be excluded or not structurally sampled: The CBP–FMO interactions are largely not dependent on their relative positions, at least based on an idealized FRET model.…”

“…The above results, namely, Figure 2 and the robustness found in Figure 4, allow us to estimate an "FMO Forster radius": Figure 2B shows, for our initial geometry, that E FRET,Donor of the CBP BChls drops below 0.5 at about 91.5 Å distance; hence 91.5 Å should roughly correspond to the R 0 of the full FMO complex (in the X and Y direction). From the recent FMO−RC structure, 51 it is known that the distance between two FMO units is about 100 Å. Plotting the FMO FRET efficiency curves (using eq 1) for two adjacent FMO units at a 100 Å distance yields the graph shown in Figure 5. Once E FRET,Donor drops below 97.5% for one unit, the other FMO unit takes over.…”