Deoxymyoglobin

FIGURE 15.27 The displaceiTient of the Fe ion of the heme of deoxymyoglobin from the plane of the porphyrin ring system by the pull of His F8. In oxymyoglobin, the bound O9 counteracts this effect. 

Polycrystalline Material Versus Frozen Solution (Example Picket-Fence Porphyrin and Deoxymyoglobin)... 

Frozen solution of deoxymyoglobin (Mb) has been the subject of an NFS investigation in the temperature range 3.2-230 K (Fig. 9.6) [15]. The synchrotron pulses were transmitted through the entrance window of the sample with a size of 12 mm 2 mm (width height). By scanning the sample area with a narrow beam (about 1 mm 0.3 mm), the homogeneity of the effective thickness was determined as 2.5%, which is more than ten times better than in the aforementioned case. 

Fig. 9.6 Measured NFS spectra of deoxymyoglobin at the indicated temperatures. The solid lines are the simulations obtained with SYNFOS [13, 14] using the Debye model for the effective thickness as described in the text. Taken from [15]...

Temperature-Dependent Quadrupole Splitting in Paramagnetic (S = 2) Iron Compounds (Example Deoxymyoglobin)... 

An excellent example of a simple second-order reaction being far from simple is the interaction of small molecules e. g. O2, CO or NO with deoxymyoglobin (PFe). Examination... 

Deoxymyoglobin has an excited state spectrum without any strong ground state bleaching. Thus, the 450 absorption band and a broad band at 600-650 nm can be seen but the fused Q band in the ground state must be counterbalanced by a like absorption in the excited state so that no bleaching is seen in the 500-570 nm range. The decay from the excited state occurs with a 34 psec time constant in the 460 nm excited state absorption band but is delayed to 60 psec in the broad 600 nm absorption band as shown in Fig. 4. 

Although there is a similarity in the pattern of the isotropic shifts of the high-spin iron(II) porphyrins in the aqueous micellar and benzene solutions, some differences are also noticeable. First, the heme proton resonances in the micelle are much broader than in benzene, and resemble those reported for deoxymyoglobin [62]. Second, the downfield shift of the methyl resonances in... 

Parak, R, Knapp, E. W., and Kucheida, D. 1982. Protein dynamics. Mossbauer spectroscopy on deoxymyoglobin crystals. J. Mol. Biol. 161 177-94. 

Heme from metmyoglobin, oxymyoglobin, or deoxymyoglobin (or hemoglobin) was not extracted. 

Mb11 = deoxymyoglobin, Mbn02 = oxymyoglobin, Hbm(H20) = ferrimyo-globin, MbmCN = cyanoferrimyoglobin. 

In the NMR spectrum of deoxymyoglobin some resonances at low fields from —10 ppm (Fig. 31) and at high fields from DSS were found to be shifted by hyperfine interactions with the paramagnetic heme iron. There are fewer resolved lines than in cyanoferrimyoglobin (Fig. 14),... 

Fig. 30. Proton NMR spectra between +4 and —10 ppm of deoxymyoglobin (Mb) and oxymyoglobin (MbC>2) from sperm whale...

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