TY - JOUR
T1 - Dynamic structural disorder of the FeO2 moiety in oxymyoglobin studied by nuclear resonant forward scattering of synchrotron radiation
AU - Herta, C.
AU - Winkler, H.
AU - Benda, R.
AU - Haas, M.
AU - Trautwein, A. X.
PY - 2002/10/1
Y1 - 2002/10/1
N2 - Oxy- as well as deoxymyoglobin exhibit a pronounced temperature dependence of the quadrupole splitting of the heme iron as detected by conventional Mössbauer spectroscopy. With nuclear resonant forward scattering (NFS) of synchrotron radiation, which can be viewed as Mössbauer spectroscopy in the time domain, it is shown that this spectroscopic behavior, although it is phenomenologically similar in the two cases, is based on completely different physical mechanisms. It is demonstrated that stochastic fluctuations of the iron electric field gradient in MbO2, which are due to the dynamic structural disorder of the FeO2 moiety, are the reason for the temperature-dependent alterations of the coherent quantum beat pattern in the NFS spectra of MbO2, in contrast to deoxyMb where transitions between orbital states of iron take place. This subtle spectroscopic difference cannot be inferred from conventional Mössbauer spectroscopy.
AB - Oxy- as well as deoxymyoglobin exhibit a pronounced temperature dependence of the quadrupole splitting of the heme iron as detected by conventional Mössbauer spectroscopy. With nuclear resonant forward scattering (NFS) of synchrotron radiation, which can be viewed as Mössbauer spectroscopy in the time domain, it is shown that this spectroscopic behavior, although it is phenomenologically similar in the two cases, is based on completely different physical mechanisms. It is demonstrated that stochastic fluctuations of the iron electric field gradient in MbO2, which are due to the dynamic structural disorder of the FeO2 moiety, are the reason for the temperature-dependent alterations of the coherent quantum beat pattern in the NFS spectra of MbO2, in contrast to deoxyMb where transitions between orbital states of iron take place. This subtle spectroscopic difference cannot be inferred from conventional Mössbauer spectroscopy.
UR - http://www.scopus.com/inward/record.url?scp=0036823738&partnerID=8YFLogxK
U2 - 10.1007/s00249-002-0237-z
DO - 10.1007/s00249-002-0237-z
M3 - Journal articles
C2 - 12355257
AN - SCOPUS:0036823738
SN - 0175-7571
VL - 31
SP - 478
EP - 484
JO - European Biophysics Journal
JF - European Biophysics Journal
IS - 6
ER -