View source for 2glk

[[Image:2glk.gif|left|200px]]<br /><applet load="2glk" size="450" color="white" frame="true" align="right" spinBox="true" 
caption="2glk, resolution 0.94&Aring;" />
'''High-resolution study of D-Xylose isomerase, 0.94A resolution.'''<br />

==Overview==
Time-of-flight neutron diffraction has been used to locate hydrogen atoms, that define the ionization states of amino acids in crystals of D-xylose, isomerase. This enzyme, from Streptomyces rubiginosus, is one of the, largest enzymes studied to date at high resolution (1.8 A) by this method., We have determined the position and orientation of a metal ion-bound water, molecule that is located in the active site of the enzyme; this water has, been thought to be involved in the isomerization step in which D-xylose is, converted to D-xylulose or D-glucose to D-fructose. It is shown to be, water (rather than a hydroxyl group) under the conditions of measurement, (pH 8.0). Our analyses also reveal that one lysine probably has an, -NH(2)-terminal group (rather than NH(3)(+)). The ionization state of each, histidine residue also was determined. High-resolution x-ray studies (at, 0.94 A) indicate disorder in some side chains when a truncated substrate, is bound and suggest how some side chains might move during catalysis., This combination of time-of-flight neutron diffraction and x-ray, diffraction can contribute greatly to the elucidation of enzyme, mechanisms.

==About this Structure==
2GLK is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptomyces_rubiginosus Streptomyces rubiginosus] with MN and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Xylose_isomerase Xylose isomerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=5.3.1.5 5.3.1.5] Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2GLK OCA]. 

==Reference==
Locating active-site hydrogen atoms in D-xylose isomerase: time-of-flight neutron diffraction., Katz AK, Li X, Carrell HL, Hanson BL, Langan P, Coates L, Schoenborn BP, Glusker JP, Bunick GJ, Proc Natl Acad Sci U S A. 2006 May 30;103(22):8342-7. Epub 2006 May 17. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=16707576 16707576]
[[Category: Single protein]]
[[Category: Streptomyces rubiginosus]]
[[Category: Xylose isomerase]]
[[Category: Bunick, G.J.]]
[[Category: Carrell, H.L.]]
[[Category: Glusker, J.P.]]
[[Category: Hanson, B.L.]]
[[Category: Harp, J.M.]]
[[Category: Katz, A.K.]]
[[Category: GOL]]
[[Category: MN]]
[[Category: beta-alpha-barrels]]
[[Category: tim barrel]]
[[Category: two metal binding sites]]

''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 11:15:49 2007''