1tvs
From Proteopedia
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TRIFLUOROETHANOL STABILIZES A HELIX-TURN-HELIX MOTIF IN EQUINE INFECTIOUS-ANEMIA-VIRUS TRANS-ACTIVATOR PROTEIN
Overview
The solution structure of the 75-amino-acid trans-activator (Tat) protein of the equine infectious-anemia virus in trifluoroethanol-containing solution was determined by two-dimensional and three-dimensional nuclear magnetic resonance spectroscopy, resulting in a total of 838 nuclear-Over-hauser-enhancement distance restraints, and restrained molecular-dynamics simulations. In contrast to the recently determined structure of this protein in trifluoroethanol-free pH 6.3 solution, the hydrophobic core and the adjacent basic RNA-binding region of the protein showed well-defined alpha-helical secondary structure in trifluoroethanol-containing solution. The helical regions comprise those parts of the molecule whose helix-forming tendencies were noted earlier in trifluoroethanol-free solution. Two helices (Gln38-Arg43 and Asp48-Ala64) are connected by a tight type-II turn centered at the strictly conserved Gly46 leading to a helix-turn-helix motif in the core and basic region of the protein. A third helix (Thr9-Asn13) is located in the less well defined N-terminal part of the protein. These observations may support the notion that the protein adopts a helical structure in the RNA-binding region on complex formation. Although the secondary-structure elements become better defined in trifluoroethanol-containing solution, the opposite is true for the hydrophobically stabilized tertiary structure. This adds a caveat to studies of protein structures in trifluoroethanol-containing solution in general.
About this Structure
1TVS is a Single protein structure of sequence from Equine infectious anemia virus. Full crystallographic information is available from OCA.
Reference
Trifluoroethanol stabilizes a helix-turn-helix motif in equine infectious-anemia-virus trans-activator protein., Sticht H, Willbold D, Ejchart A, Rosin-Arbesfeld R, Yaniv A, Gazit A, Rosch P, Eur J Biochem. 1994 Nov 1;225(3):855-61. PMID:7957222
Page seeded by OCA on Thu Feb 21 15:17:51 2008
