TY  - JOUR
AU  - Casadei, C. M.
AU  - Gumiero, A.
AU  - Metcalfe, C. L.
AU  - Murphy, E. J.
AU  - Basran, J.
AU  - Concilio, M. G.
AU  - Teixeira, S. C. M.
AU  - Schrader, T. E.
AU  - Fielding, A. J.
AU  - Ostermann, A.
AU  - Blakeley, M. P.
AU  - Raven, E. L.
AU  - Moody, P. C. E.
TI  - Neutron cryo-crystallography captures the protonation state of ferryl heme in a peroxidase
JO  - Science
VL  - 345
IS  - 6193
SN  - 1095-9203
CY  - Washington, DC [u.a.]
PB  - American Association for the Advancement of Science64196
M1  - FZJ-2015-01833
SP  - 193 - 197
PY  - 2014
AB  - Heme enzymes activate oxygen through formation of transient iron-oxo (ferryl) intermediates of the heme iron. A long-standing question has been the nature of the iron-oxygen bond and, in particular, the protonation state. We present neutron structures of the ferric derivative of cytochrome c peroxidase and its ferryl intermediate; these allow direct visualization of protonation states. We demonstrate that the ferryl heme is an Fe(IV)=O species and is not protonated. Comparison of the structures shows that the distal histidine becomes protonated on formation of the ferryl intermediate, which has implications for the understanding of O–O bond cleavage in heme enzymes. The structures highlight the advantages of neutron cryo-crystallography in probing reaction mechanisms and visualizing protonation states in enzyme intermediates.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000339409900048
C6  - pmid:25013070
DO  - DOI:10.1126/science.1254398
UR  - https://juser.fz-juelich.de/record/188457
ER  -