Myoglobin solution

Fig. 6.28 From bottom to top effective diffusion constant from NSE experiments, S(Q) deduced from RMS A fits, and DqH(Q)=D(Q)S(Q) with H(Q) the hydrodynamic factor. The left side corresponds to a myoglobin solution of concentration c=14.7 mM and the right side c=30 mM. Note the strong reduction of the value of D upon concentration increase. (Reprinted with permission from [332]. Copyright 2003 Elsevier)...

Fading of acetone extracts of pure NO-myoglobin solutions could be prevented by adding 1 ml of fresh 0.5% neutralized cysteine hydrochloride to 9 ml of NO-myoglobin solution. 

Measure protein concentration of myoglobin solution (see Basic Protocol 1, step 9) and freeze in aliquots at -80°C. 

Using gravity flow, pass the myoglobin solution over a Sephadex G-25 desalting column to remove excess hydrosulfite. 

Alternatively, excess hydrosulfite may be removed from the myoglobin solution via dialysis against the buffer of choice (1 vol protein 10 vol buffer, 3 times, 8 hr each) or via mixed-bed ion-exchange chromatography (e.g., AG501-X8, Bio-Rad) (Brown and Mebine, 1969). 

Figure F3.3.2 Absorbance spectra for myoglobin solutions containing different proportions of oxy-and metmyoglobin.

The amount of tightly bound water (water of hydration) present in the myoglobin solution can be calculated from the amplitude of the S dispersion using a method previously described (1,10). From the value of 3.6 for this parameter (Table I) a value of hydration of 0.15-0.02 unit mass of water per unit mass of myoglobin is obtained. Considered as a volume fraction of the total water content this would amount to about 4%, which compares well with the figure of 5% recently proposed for muscle fibres by Foster, Schepps and Schwan (16). 

Zhao et al. [104] reported the electrochemical behavior of myoglobin on MWCNT-GCE and the potential application for the development of a nitric oxide biosensor. Myoglobin was immobilized on the acid-treated-MWCNTs-GCE by dipping the electrode into 0.24 mM myoglobin solution (in acetate buffer pH 5.6) over 72 hours. After that, the electrode was removed, washed with water and stored at 4 °C. Electrochemical impedance spectroscopy experiments... 

Figure 9. (a) Ultraviolet spectrum (zeroed at 350 nm) of a standard avidin solution (10 M in 0.2 M ammonium carbonate buffer at pH 8.9) relative to the buffer solution, (b) Ultraviolet—visible spectrum (zeroed at SSO nm) of a standard myoglobin solution (10 M in 0.2 M ammonium carbonate buffer at pH 8.9) relative to the buffer solution. Contimied on next page. 

Figure 9. Continued, (c) Ultraviolet—visible spectrum of the supernatant after affinity precipitation of avidin from an avidin—myoglobin solution (both 10" M in 0.2 M ammonium carbonate buffer at pH 8.9) by a DMPE-B-C12E8 solution. The supernatant was sampled after precipitation for two hours and centrifugation at 5000 rpm for twenty minutes, (d) Ultraviolet—visible spectrum of avidin—DMPE-B precipitate described in text and caption 9(c) after resuspension in 10" M C12E8 solution in 0.2 M ammonium carbonate buffer at pH 8.9.

The MS system was initially tuned with a MRFA/myoglobin solution by a flow injection pump and afterwards with a solution of estrone with concentration 5 mg/1 to improve sensitivity. 

Figure 8.3. The real part of the complex frequency-dependent dielectric function [e (co)] of aqueous myoglobin solution for different concentrations. Concentrations are (from top to bottom) 161, 99, and 77 mg/mL at 293.15 K. The symbols denote experimental results while the solid line is a fit to the theory of dynamics exchange model developed by Nandi and Bagchi. Adapted with permission from J. Phys. Chem. A, 102 (1998), 8217-8221. Copyright (1998) American Chemical Society.

E. Dachwitz, F. Parak, and M. Stockhausen, On the dielectric relaxation of aqueous myoglobin solutions. Ber. Bunsenges. Phys. Chem., 93 (1989), 1454 S. Boresch, P. Hochtl, and O. Steinhauser, Studying the dielectric properties of a protein solution by computer simulation. J. Phys. Chem. B, 104 (2000), 8743-8752. 

GAS-LIQUID MASS TRANSFER 47 microliters of myoglobin solution... 

Jones, R, 1979. High electric field dielectric studies of aqueous myoglobin solutions. Biophys. Chem. 9,... 

In 1993, we reported [19] reversible electron transfer between electrodes and the iron heme protein myoglobin imbedded in cast multi-lameUar liquid crystal films of didodecyldimethylammonium bromide (DDAB). Heretofore, reversible electron transfer from electrodes to myoglobin in solution had been accomplished only for highly purified myoglobin solutions on specially cleaned indium tin oxide electrodes [20,21]. If enhanced electron transfer for proteins in surfactant or lipid films were to prove general, it might help solve longstanding problems in protein electrochemistry. 

CV peaks for Mb-DDAB films decreased less than 20% upon storage of the electrode in buffer for a month. A bare PG electrode placed into buffer or a myoglobin solution gives no peaks (Figs. 4a, b). 

---