Myoglobin modified

Fig. 4. Heterolytic and hemol3itic pathways of peroxide cleavage by myoglobin, (modified from Ref. 198).

Figure 11.19 (a) Schematic representation of silver NPs and myoglobin modified electrode,... 

Wright and co-authors (Wright et al. 1999) studied the properties of a polyethyle-neoxide myoglobine-modified electrode in the reductive dehalogenation of hex-achloroethane in ethanolic solutions, and the observed catalytic response resulted linearly dependent on the bulk concentration of the substrate. 

Figure 4.2. Temperature dependence of the rate constant of electron transfer (Icet) in myoglobin modified covalently by donor-acceptor groups (a) and the deviation of various dynamic quantities from normal harmonic behaviour obtained by molecular dynamic simulation, inelastic neutron scattering, MOssbauer spectroscopy and spectral broadening analysis (b). (Likhtenshtein et al., 2000). Reproduced with permission.

EJectron-tunneling pathway for myoglobin modified at His-48, The pathway moves along the protein backbone from His-48 to Arg-45, and then to the heme via an H-bond (=) to the heme propionate. The His-48 to heme edge-edge distance is 12.7 A. ... 

PSS-SG composite film was tested for sorption of heme proteins hemoglobin (Hb) and myoglobin (Mb). The peroxidaze activity of adsorbed proteins were studied and evaluated by optical and voltammetric methods. Mb-PSS-SG film on PG electrode was shown to be perspective for detection of dissolved oxygen and hydrogen peroxide by voltammetry with linear calibration in the range 2-30 p.M, and detection limit -1.5 p.M. Obtained composite films can be modified by different types of biological active compounds which is important for the development of sensitive elements of biosensors. 

Shire, SJ Hanania, GIH Gurd, FRN, Electrostatic Effects in Myoglobin. Application of the Modified Tanford-Kirkwood Theory to Myoglobins from Elorse, California Grey Whale, Harbor Seal, and California Sea Lion, Biochemistry 14, 1352, 1975. 

G.C. Zhao, L. Zhang, X.W. Wei, Z.S. Yang, Myoglobin on multi-walled carbon nanotubes modified electrode direct electrochemistry and electrocatalysis. Electrochem. Commun. 5, 825—829 (2003). 

Y.D. Jin, Y. Shao, and S.J. Dong, Direct electrochemistry and surface plasmon resonance characterization of alternate layer-by-layer self-assembled DNA-myoglobin thin films on chemically modified gold surfaces. Langmuir 19, 4771—4777 (2003). 

J.F. Stargardt, F.M. Fiawkridge, and H.L. Landrum, Reversible heterogeneous reduction and oxidation of sperm whale myoglobin at a surface modified gold minigrid electrode. Anal. Chem. 50, 930-932 (1978). 

J. Ye and R.P. Baldwin, Catalytic reduction of myoglobin and haemoglobin at chemically modified electrodes containing methylene blue. Anal. Chem. 60, 2263—2268 (1988). 

A similar study was performed on ruthenium-modified myoglobins, in which AG variations were obtained by changing the nature of the ruthenium complex covalently bound to the protein, and by substituting a porphyrin to the heme [137]. It is gratifying to observe that, in spite of the rather heterogeneous character of this series, the study leads to an estimation of 1.9 to 2.4 eV for A which is consistent with the value 2.3 eV derived in section 3.2.1 from temperature dependent experiments. Satisfactory agreement between the results given by the two methods is also observed in the case of ruthenium-modified cytochrome c [138]. 

Fig. 8. A view into the interior of a ruthenium modified myoglobin where the amino acids in the vicinity of Trp-14 are shown. The dots correspond to the statistieal density Pn i,(r) of (discretized) tunneling path vertices (rj in Eq. 26) from 500,000 tunneling paths [19], The (r) is clustered in a cylindrical zone centered on the average path, shown as the light line appearing in the center and emerging toward the viewer. The computation modeled paths of electron transfer in Ru(His-12) myoglobin studied experimentally by Gray and coworkers [88]...

A variety of physical methods has been used to ascertain whether or not surface ruthenation alters the structure of a protein. UV-vis, CD, EPR, and resonance Raman spectroscopies have demonstrated that myoglobin [14, 18], cytochrome c [5, 16, 19, 21], and azurin [13] are not perturbed structurally by the attachment of a ruthenium complex to a surface histidine. The reduction potential of the metal redox center of a protein and its temperature dependence are indicators of protein structure as well. Cyclic voltammetry [5, 13], differential pulse polarography [14,21], and spectroelectrochemistry [12,14,22] are commonly used for the determination of the ruthenium and protein redox center potentials in modified proteins. 

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