View source for 2ara

[[Image:2ara.gif|left|200px]]<br /><applet load="2ara" size="450" color="white" frame="true" align="right" spinBox="true" 
caption="2ara, resolution 2.8&Aring;" />
'''APO FORM OF ESCHERICHIA COLI REGULATORY PROTEIN ARAC'''<br />

==Overview==
The crystal structure of the arabinose-binding and dimerization domain of, the Escherchia coli gene regulatory protein AraC was determined in the, presence and absence of L-arabinose. The 1.5 angstrom structure of the, arabinose-bound molecule shows that the protein adopts an unusual fold, binding sugar within a beta barrel and completely burying the arabinose, with the amino-terminal arm of the protein. Dimer contacts in the presence, of arabinose are mediated by an antiparallel coiled-coil. In the 2.8, angstrom structure of the uncomplexed protein, the amino-terminal arm is, disordered, uncovering the sugar-binding pocket and allowing it to serve, as an oligomerization interface. The ligand-gated oligomerization as seen, in AraC provides the basis of a plausible mechanism for modulating the, protein's DNA-looping properties.

==About this Structure==
2ARA is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2ARA OCA]. 

==Reference==
Structural basis for ligand-regulated oligomerization of AraC., Soisson SM, MacDougall-Shackleton B, Schleif R, Wolberger C, Science. 1997 Apr 18;276(5311):421-5. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=9103202 9103202]
[[Category: Escherichia coli]]
[[Category: Single protein]]
[[Category: Soisson, S.M.]]
[[Category: Wolberger, C.]]
[[Category: carbohydrate binding]]
[[Category: coiled-coil]]
[[Category: jelly-roll]]
[[Category: transcription regulation]]

''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 08:18:56 2007''