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Biology subjects

Fuertges, T.

Publications and source records attributed to Fuertges, T..

2 recordsLinked to original sources

kontakteUR: transforming coordinates to chemical intuition to focus on essential interactions in biomolecular systems

Molecular interactions govern cellular function, making them essential to discover biomolecular mechanisms by unravelling structure-function relationships. The rapid growth of AI-based prediction, experimental determination, and molecular dynamics simulations generates structural data at an unprecedented scale. However, structural information is typically represented as Cartesian coordinates, leaving chemical interactions and conformational relationships largely implicit. We introduce a high-throughput framework transforming structural geometry into a standardized, compact contact space. Moving beyond simple distance cutoffs, it provides a chemically and geometrically informed representation of various residue-residue interactions, their temporal changes, and conformations at residue-level resolution. Our contact-space representation enables systematic comparison and classification even for large-scale analysis. Case studies spanning structure comparison or studies of protein-protein, protein-ligand, protein-RNA, and antibody-antigen complexes, demonstrate how contact-space analysis reveals interaction patterns, identifies key mutation sites, and links structural features to experimental observations. With these and further applications, kontakteUR elucidates biomolecular function and assists targeted protein design, with results suited for further processing by artificial intelligence algorithms.

biochemistry↗

Structural insights into late-stage photosystem II assembly by Psb32

Photosystem II (PSII) assembly is a stepwise process in which intermediate complexes with auxiliary proteins are transiently formed to allow efficient de novo biogenesis or repair of damaged PSII. In particular, the role of extrinsic PSII subunits (PsbO, PsbU, PsbV) and auxiliary proteins such as Psb27 for the formation and photoactivation of the Mn4O5Ca cluster, which catalyzes the unique water splitting reaction in mature PSII, remains unclear. Using cryo-electron microscopy, we have determined the structure of two novel late-stage PSII assembly intermediates from Thermosynechococcus vestitus BP-1. In contrast to previous studies, the resulting monomeric PSII complexes contain both PsbJ and Psb27 and exhibit a fully mature acceptor side, while the oxygen evolving complex (OEC) is still in an immature state. The second complex additionally associates with the late-acting assembly factor Psb32 and the extrinsic subunit PsbV. While Psb32 has received little attention, its proposed role in the complex challenges the previous assumption that all extrinsic subunits associate spontaneously, as well as the notion that PsbO initiates binding and solely drives OEC formation. Our structures of the Psb27-PSII and Psb32-PSII intermediates provide novel insights, how structural changes of C-termini of the D1 and D2 core proteins regulate maturation of the OEC and how the catalytic side is prepared for binding of the Mn4O5Ca cluster. The Psb32-PSII complex potentially represents the final PSII assembly intermediate that precedes the incorporation and photoactivation of the Mn4O5Ca cluster, allowing us to explain the final steps in the PSII biogenesis and assembly pipeline in great detail, as only the two extrinsic subunits PsbO and PsbU are missing.

plant biology↗