Charged groups at binding interfaces of the PsbO subunit of photosystem II: A combined bioinformatics and simulation study.
PsbO is an extrinsic subunit of photosystem II engaged in complex binding interactions within photosystem II. At the interface between PsbO, D1 and D2 subunits of photosystem II, a cluster of charged and polar groups of PsbO is part of an extended hydrogen-bond network thought to participate in proton transfer. The precise role of specific amino acid residues at this complex binding interface remains a key open question. Here, we address this question by carrying out extensive bioinformatics analyses and molecular dynamics simulations of PsbO proteins with mutations at the binding interface. We find that PsbO proteins from cyanobacteria vs. plants have specific preferences for the number and composition of charged amino acid residues that may ensure that PsbO proteins avoid aggregation and expose long unstructured loops for binding to photosystem II. A cluster of conserved charged groups with dynamic hydrogen bonds provides PsbO with structural plasticity at the binding interface with photosystem II.
Department of Artificial Intelligence, University of Granada, E-18071 Granada, Spain. Electronic address: C.DelVal@decsai.ugr.es.
Coral
C
Del Val
Theoretical Molecular Biophysics, Department of Physics, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany. Electronic address: nbondar@zedat.fu-berlin.de.
Ana-Nicoleta
AN
Bondar
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry*; D001665:Binding Sites; D019295:Computational Biology; D017124:Conserved Sequence; D000458:Cyanobacteria / Q000737:chemistry; D066264:Datasets as Topic; D006860:Hydrogen Bonding; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D045332:Photosystem II Protein Complex / Q000737:chemistry*; D010940:Plant Proteins / Q000737:chemistry*; D011485:Protein Binding; D011487:Protein Conformation; D025941:Protein Interaction Mapping; D021122:Protein Subunits; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D055672:Static Electricity
D001426:Bacterial Proteins; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D021122:Protein Subunits