Publication Abstract from PubMed
The hybrid plasmid-virus pSSVx from Sulfolobus islandicus presents an open reading frame encoding a 76 amino acid protein, namely Stf76, that does not show significant sequence homology with any protein with known 3D structure. The recombinant protein recognizes specifically two DNA-binding sites located in its own promoter, thus suggesting an auto-regulated role of its expression. Circular dichroism, spectrofluorimetric, light scattering and isothermal titration calorimetry experiments indicated a 2:1 molar ratio (protein:DNA) upon binding to the DNA target containing a single site. Furthermore, the solution structure of Stf76, determined by nuclear magnetic resonance (NMR) using chemical shift Rosetta software, has shown that the protein assumes a winged helix-turn-helix fold. NMR chemical shift perturbation analysis has been performed for the identification of the residues responsible for DNA interaction. In addition, a model of the Stf76-DNA complex has been built using as template a structurally related homolog.
Structural and functional studies of Stf76 from the Sulfolobus islandicus plasmid-virus pSSVx: a novel peculiar member of the winged helix-turn-helix transcription factor family.,Contursi P, Farina B, Pirone L, Fusco S, Russo L, Bartolucci S, Fattorusso R, Pedone E Nucleic Acids Res. 2014 May 1;42(9):5993-6011. doi: 10.1093/nar/gku215. Epub 2014, Mar 25. PMID:24682827[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
