spacer
spacer

PDBsum entry 3kcl

Go to PDB code: 
Top Page protein ligands metals links
Isomerase PDB id
3kcl
Jmol
Contents
Protein chain
388 a.a.
Ligands
GLC
DOD ×199
Metals
_CD ×2

References listed in PDB file
Key reference
Title Metal ion roles and the movement of hydrogen during reaction catalyzed by d-Xylose isomerase: a joint X-Ray and neutron diffraction study.
Authors A.Y.Kovalevsky, L.Hanson, S.Z.Fisher, M.Mustyakimov, S.A.Mason, V.T.Forsyth, M.P.Blakeley, D.A.Keen, T.Wagner, H.L.Carrell, A.K.Katz, J.P.Glusker, P.Langan.
Ref. Structure, 2010, 18, 688-699.
PubMed id 20541506
Abstract
Conversion of aldo to keto sugars by the metalloenzyme D-xylose isomerase (XI) is a multistep reaction that involves hydrogen transfer. We have determined the structure of this enzyme by neutron diffraction in order to locate H atoms (or their isotope D). Two studies are presented, one of XI containing cadmium and cyclic D-glucose (before sugar ring opening has occurred), and the other containing nickel and linear D-glucose (after ring opening has occurred but before isomerization). Previously we reported the neutron structures of ligand-free enzyme and enzyme with bound product. The data show that His54 is doubly protonated on the ring N in all four structures. Lys289 is neutral before ring opening and gains a proton after this; the catalytic metal-bound water is deprotonated to hydroxyl during isomerization and O5 is deprotonated. These results lead to new suggestions as to how changes might take place over the course of the reaction.
PROCHECK
Go to PROCHECK summary
 Headers