%0 Journal Article %A Schneidewind, Judith %A Krause, Frank %A Bocola, Marco %A Stadler, Andreas Maximilian %A Davari, Mehdi D. %A Schwaneberg, Ulrich %A Jaeger, Karl-Erich %A Krauss, Ulrich %T Consensus model of a cyanobacterial light-dependent protochlorophyllide oxidoreductase in its pigment-free apo-form and photoactive ternary complex %J Communications biology %V 2 %N 1 %@ 2399-3642 %C London %I Springer Nature %M FZJ-2019-04514 %P 351 %D 2019 %X Photosynthetic organisms employ two different enzymes for the reduction of the C17 = C18 double bond of protochlorophyllide (Pchlide), yielding the chlorophyll precursor chlorophyllide. First, a nitrogenase-like, light-independent (dark-operative) Pchlide oxidoreductase and secondly, a light-dependent Pchlide oxidoreductase (LPOR). For the latter enzyme, despite decades of research, no structural information is available. Here, we use protein structure modelling, molecular dynamics (MD) simulations combined with multi-wavelength analytical ultracentrifugation (MWA-AUC) and small angle X-ray scattering (SAXS) experiments to derive a consensus model of the LPOR apoprotein and the substrate/cofactor/LPOR ternary complex. MWA-AUC and SAXS experiments independently demonstrate that the apoprotein is monomeric, while ternary complex formation induces dimerization. SAXS-guided modelling studies provide a full-length model of the apoprotein and suggest a tentative mode of dimerization for the LPOR ternary complex, supported by published cross-link constraints. Our study provides a first impression of the LPOR structural organization. %F PUB:(DE-HGF)16 %9 Journal Article %$ pmid:31583285 %U <Go to ISI:>//WOS:000488309300001 %R 10.1038/s42003-019-0590-4 %U https://juser.fz-juelich.de/record/864911