Apomyoglobin

The details of many all-atom unfolding simulation studies have been summarized in several reviews [17,46,47]. These studies include unfolding simulations of a-lactalbumin, lysozyme, bovine pancreatic trypsin inhibitor (BPTI), barnase, apomyoglobin, [3-lacta-mase, and more. The advantage of these simulations is that they provide much more detailed information than is available from experiment. However, it should be stressed that there is still only limited evidence that the pathways and intermediates observed in the nanosecond unfolding simulations correlate with the intermediates observed in the actual experiments. 

Apomyoglobin Provides a Hindered Environment for Heme Iron... 

Privalov et al (1989) studied the unfolded forms of several globular proteins [ribonuclease A, hen egg white lysozyme, apomyoglobin (apoMb), cytochrome c, and staphylococcal nuclease]. Unfolding was induced by 6 M Gdm-HCl at 10°C, heating to 80°C, or by low pH at 10°C with cross-links cleaved (reduction and carboxamidomethylation or removal of heme). The unfolded forms showed CD spectra (Fig. 27)... 

Fig. 41. Near-UV CD spectra of /1-lactamase (A) and apomyoglobin (B) in native state...

Fig. 2. (Left) 750-MHz 15N- H HSQC spectrum and (right) 750-MHz HNCO spectrum of apomyoglobin at pH 2.3,10 mM acetate-

Fig. 3. Secondary chemical shifts for 13C , 13CO, H , and 13C as a function of residue number in apomyoglobin at pH 4.1. Bars at the top of the figure indicate the presence of NOEs the smaller bars indicate that the NOE was ambiguous due to resonance overlap. Black rectangles at the base of the top panel indicate the locations of helices in the native holomyoglobin structure (Kuriyan et al, 1986). Hashed rectangles indicate putative boundaries for helical regions in the pH 4 intermediate, based on the chemical shift and NOE data. Reproduced from Eliezer et al (2000). Biochemistry 39, 2894-2901, with permission from the American Chemical Society.

Fig. 4. Spectral densities of backbone motions in the pH 4.1 apomyoglobin intermediate at three different frequencies. Reproduced from Eliezer et al. (2000). Biochemistry 39, 2894-2901, with permission from the American Chemical Society.

A. Probing the Protein Folding Landscape Equilibrium NMR Studies of Apomyoglobin... 

C.H. Lochmiiller and S.S. Saavedra, Intrinsic florescence characteristics of apomyoglobin adsorbed to microparticulate silica, Langmuir, 3 (1987) 433. C.H. Lochmiiller and S.S. Saavedra, Interconversion of conformation of apomyoglobin adsorbed on hydrophobic silica gel, J. Am. Chem. Soc., 109... 

Curve D pyranine in the heme binding site of apomyoglobin, a site containing 30 water molecules or less. 

Kolsenik J, Belgorodsky B, Fadeev L, Gozin M (2007) Can apomyoglobin form a complex with a spherical ligand Interactions between apomyoglobin and [C60] fullerene derivative. J. Nanosci. Nanotechnol. 7 1389-1394. 

Eliezer D., Yao J., Dyson H. J. and Wright P. E. Structural and dynamic characterization of partially folded states of apomyoglobin and implications for protein folding. Nat. Struct. Biol. (1998) 5(2) 148-155. 

Ballew R. M., Sabelko J. and Gruebele M. Direct observation of fast protein folding the initial collapse of apomyoglobin. Proc. Natl. Acad. Sri., USA (1996) 93 5759-5764. 

Gilmanshin R., Williams S., Callender R. H., Woodruff W. H. and Dyer R. B. Fast events in protein folding relaxation dynamics of secondary and tertiary structure in native apomyoglobin. Proc. Natl. Acad. Sci., USA (1997) 94(8) 3709-3713. 

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