Changes in non-core regions stabilise plastocyanin from the thermophilic cyanobacterium Phormidium laminosum

Francisco J. Muñoz-López, Simone Raugei, Miguel A. De La Rosa, Antonio J. Díaz-Quintana, Paolo Carloni

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4 Citations (Scopus)


We report a theoretical investigation on the different stabilities of two plastocyanins. The first one belongs to the thermophilic cyanobacterium Phormidium laminosum and the second one belongs to its mesophilic relative Synechocystis sp. These proteins share the same topology and secondary-structure elements; however, the melting temperatures of their oxidised species differ by approximately 15 K. Long-time-scale molecular dynamics simulations, performed at different temperatures, show that the thermophilic protein optimises a set of intramolecular interactions (interstrand hydrogen bonding, salt bridging and hydrophobic clustering) within the region that comprises the strands β5 and β6, loop L5 and the helix. This region exhibits most of the differences in the primary sequence between the two proteins and, in addition, it is involved in the interaction with known physiological partners. Further work is in progress to unveil the specific structural features responsible for the different thermal stability of the two proteins.

Original languageEnglish
Pages (from-to)329-338
Number of pages10
JournalJournal of Biological Inorganic Chemistry
Issue number3
Publication statusPublished - Mar 2010



  • Blue copper protein
  • Molecular dynamics
  • Plastocyanin
  • Protein stability
  • Thermophilic cyanobacteria

ASJC Scopus subject areas

  • Biochemistry
  • Inorganic Chemistry

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