PMID- 16551107
OWN - NLM
STAT- MEDLINE
DCOM- 20060525
LR  - 20181113
IS  - 0002-7863 (Print)
IS  - 1520-5126 (Electronic)
IS  - 0002-7863 (Linking)
VI  - 128
IP  - 12
DP  - 2006 Mar 29
TI  - Dynamics of proteins encapsulated in silica sol-gel glasses studied with IR 
      vibrational echo spectroscopy.
PG  - 3990-7
AB  - Spectrally resolved infrared stimulated vibrational echo spectroscopy is used to 
      measure the fast dynamics of heme-bound CO in carbonmonoxy-myoglobin (MbCO) and 
      -hemoglobin (HbCO) embedded in silica sol-gel glasses. On the time scale of 
      approximately 100 fs to several picoseconds, the vibrational dephasing of the 
      heme-bound CO is measurably slower for both MbCO and HbCO relative to that of 
      aqueous protein solutions. The fast structural dynamics of MbCO, as sensed by the 
      heme-bound CO, are influenced more by the sol-gel environment than those of HbCO. 
      Longer time scale structural dynamics (tens of picoseconds), as measured by the 
      extent of spectral diffusion, are the same for both proteins encapsulated in 
      sol-gel glasses compared to that in aqueous solutions. A comparison of the 
      sol-gel experimental results to viscosity-dependent vibrational echo data taken 
      on various mixtures of water and fructose shows that the sol-gel-encapsulated 
      MbCO exhibits dynamics that are the equivalent of the protein in a solution that 
      is nearly 20 times more viscous than bulk water. In contrast, the HbCO dephasing 
      in the sol-gel reflects only a 2-fold increase in viscosity. Attempts to alter 
      the encapsulating pore size by varying the molar ratio of silane precursor to 
      water (R value) used to prepare the sol-gel glasses were found to have no effect 
      on the fast or steady-state spectroscopic results. The vibrational echo data are 
      discussed in the context of solvent confinement and protein-pore wall 
      interactions to provide insights into the influence of a confined environment on 
      the fast structural dynamics experienced by a biomolecule.
FAU - Massari, Aaron M
AU  - Massari AM
AD  - Department of Chemistry, Stanford University, Stanford, California 94305, USA.
FAU - Finkelstein, Ilya J
AU  - Finkelstein IJ
FAU - Fayer, Michael D
AU  - Fayer MD
LA  - eng
GR  - 2 R01 GM-061137-05/GM/NIGMS NIH HHS/United States
GR  - 1 F32 GM-071162-01/GM/NIGMS NIH HHS/United States
GR  - R01 GM061137/GM/NIGMS NIH HHS/United States
GR  - F32 GM071162/GM/NIGMS NIH HHS/United States
GR  - R01 GM061137-02/GM/NIGMS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PL  - United States
TA  - J Am Chem Soc
JT  - Journal of the American Chemical Society
JID - 7503056
RN  - 0 (Myoglobin)
RN  - 0 (carboxymyoglobin)
RN  - 42VZT0U6YR (Heme)
RN  - 7631-86-9 (Silicon Dioxide)
RN  - 9061-29-4 (Carboxyhemoglobin)
SB  - IM
MH  - Carboxyhemoglobin/*chemistry
MH  - Glass
MH  - Heme/chemistry
MH  - Myoglobin/*chemistry
MH  - Silicon Dioxide/*chemistry
MH  - Spectrophotometry, Infrared/*methods
MH  - Spectroscopy, Fourier Transform Infrared
MH  - Static Electricity
PMC - PMC2532503
MID - NIHMS63155
EDAT- 2006/03/23 09:00
MHDA- 2006/05/26 09:00
PMCR- 2008/09/08
CRDT- 2006/03/23 09:00
PHST- 2006/03/23 09:00 [pubmed]
PHST- 2006/05/26 09:00 [medline]
PHST- 2006/03/23 09:00 [entrez]
PHST- 2008/09/08 00:00 [pmc-release]
AID - 10.1021/ja058745y [doi]
PST - ppublish
SO  - J Am Chem Soc. 2006 Mar 29;128(12):3990-7. doi: 10.1021/ja058745y.