TY - JOUR AU - Schneidewind, Judith AU - Krause, Frank AU - Bocola, Marco AU - Stadler, Andreas Maximilian AU - Davari, Mehdi D. AU - Schwaneberg, Ulrich AU - Jaeger, Karl-Erich AU - Krauss, Ulrich TI - Consensus model of a cyanobacterial light-dependent protochlorophyllide oxidoreductase in its pigment-free apo-form and photoactive ternary complex JO - Communications biology VL - 2 IS - 1 SN - 2399-3642 CY - London PB - Springer Nature M1 - FZJ-2019-04514 SP - 351 PY - 2019 AB - 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. LB - PUB:(DE-HGF)16 C6 - pmid:31583285 UR - <Go to ISI:>//WOS:000488309300001 DO - DOI:10.1038/s42003-019-0590-4 UR - https://juser.fz-juelich.de/record/864911 ER -