Observation of a new oxygen-isotope-sensitive Raman band for oxyhemoproteins and its implications in heme pocket structures
- Okazaki National Research Inst. (Japan) Graduate Univ. for Advanced Studies, Okazaki (Japan)
- Argonne National Lab., IL (United States)
- Himeji Inst. of Technology, Hyogo (Japan)
A new oxygen-isotope-sensitive Raman band was found for oxyhemoglobin (HbO[sub 2]) and oxycytochrome c oxidase (CcO[center dot]O[sub 2]) in the frequency region lower than the Fe-O[sub 2] stretching mode ([nu][sub Fe-O2]). This band was located at 425 cm[sup [minus]1] for Hb[sup 16]O[sub 2] and shifted to 405 cm[sup [minus]1] with Hb[sup 18]O[sub 2] and to approximately 423 and approximately 407 cm[sup [minus]1] with Hb[sup 16]O[sup 18]O. The corresponding band appeared at 435 cm[sup [minus]1] for CcO[center dot][sup 16]O[sub 2] and shifted to 415 cm[sup [minus]1] with CcO[center dot][sup 18]O[sub 2]. Accordingly, the band has been assigned to the Fe-O-O bending mode (delta[sub FeOO]). However, the corresponding band could not be identified for oxymyoglobin (MbO[sub 2]). The Fe-O[sub 2] stretching mode ([nu][sub Fe-O2]) was observed at 568, 567, 544, and 544 cm[sup [minus]1] for Hb[sup 16]O[sub 2], Hb[sup 16]O[sup 18]O, Hb[sup 18]O[sup 16]O, and Hb[sup 18]O[sub 2], respectively, and the corresponding modes were observed at 571, 569, 547, and 545 cm[sup [minus]1] for MbO[sub 2] and 571, 567, 548, and 544 cm[sup [minus]1] for CcO[center dot]O[sub 2]. The [nu][sub Fe-O(2)] bandwidths of HbO[sub 2] and MbO[sub 2] were alike and 1.5 times broader than that of CcO-O[sub 2], suggesting that the Fe-O-O geometry is more nearly fixed in the latter. 44 refs., 6 figs., 1 tab.
- OSTI ID:
- 6735947
- Journal Information:
- Journal of the American Chemical Society; (United States), Journal Name: Journal of the American Chemical Society; (United States) Vol. 116:23; ISSN JACSAT; ISSN 0002-7863
- Country of Publication:
- United States
- Language:
- English
Similar Records
Laser-induced fluorescence excitation spectra of tert-butoxy and 2-butoxy radicals
Resonance Raman spectroscopic characterization of compound III of lignin peroxidase
Related Subjects
400201* -- Chemical & Physicochemical Properties
550200 -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
CARBOXYLIC ACIDS
ENZYMES
EVEN-EVEN NUCLEI
GLOBINS
HEME
HEMOGLOBIN
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
ISOTOPE EFFECTS
ISOTOPES
LIGHT NUCLEI
MOLECULAR STRUCTURE
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDOREDUCTASES
OXYGEN 18
OXYGEN ISOTOPES
PIGMENTS
PORPHYRINS
PROTEINS
RAMAN SPECTRA
SPECTRA
STABLE ISOTOPES