2c41: Difference between revisions

DNA-binding proteins from starved cells (Dps proteins) protect bacteria, primarily from oxidative damage. They are composed of 12 identical, subunits assembled with 23-symmetry to form a compact cage-like structure, known to be stable at temperatures > 70 degrees C and over a wide pH, range. Thermosynechococcus elongatus Dps thermostability is increased, dramatically relative to mesophilic Dps proteins. Hydrophobic interactions, at the dimeric and trimeric interfaces called Dps-like are replaced by, salt bridges and hydrogen bonds, a common strategy in thermophiles., Moreover, the buried surface area at the least-extended Dps-like interface, is significantly increased. A peculiarity of T. elongatus Dps is the, presence of a chloride ion coordinated with threefold symmetry-related, arginine residues lining the opening of the Dps-like pore toward the, internal cavity. T. elongatus Dps conserves the unusual intersubunit, ferroxidase centre that allows the Dps protein family to oxidize Fe(II), with hydrogen peroxide, thereby inhibiting free radical production via, Fenton chemistry. This catalytic property is of special importance in T., elongatus (which lacks the catalase gene) in the protection of DNA and, photosystems I and II from hydrogen peroxide-mediated oxidative damage.

2C41 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermosynechococcus_elongatus Thermosynechococcus elongatus] with CL, PG4 and PGE as [http://en.wikipedia.org/wiki/ligands ligands]. Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2C41 OCA].  

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