Protein dependence

X-ray structures are determined at different levels of resolution. At low resolution only the shape of the molecule is obtained, whereas at high resolution most atomic positions can be determined to a high degree of accuracy. At medium resolution the fold of the polypeptide chain is usually correctly revealed as well as the approximate positions of the side chains, including those at the active site. The quality of the final three-dimensional model of the protein depends on the resolution of the x-ray data and on the degree of refinement. In a highly refined structure, with an R value less than 0.20 at a resolution around 2.0 A, the estimated errors in atomic positions are around 0.1 A to 0.2 A, provided the amino acid sequence is known. 

In theory, SEC of proteins depends only on their molecular size. Sometimes the size of a protein varies with the ionic strength of the buffer (5,6). The concentration of salt not only affects the conformation of the protein, but can also influence the chromatographic separation itself. Additional retention... 

Section 6.1 considered the noncovalent binding energies that stabilize a protein strnctnre. However, the folding of a protein depends ultimately on the difference in Gibbs free energy (AG) between the folded (F) and unfolded (U) states at some temperature T ... 

The efficient uptake of precursor proteins depends on their presentation in a translocation competent state. This is maintained in vivo by the specific interaction with a highly conserved group of proteins, the heat-shock or stress related proteins (hps70s). These act as molecular chaperones and interact with the proteins to maintain them in a correctly folded state, a process which is ATP dependent. 

After mRNA splicing, the tropoelastin mRNA is translated at the surface of the rough endoplasmic reticulum (RER) in a variety of cells smooth muscle cells, endothelial and microvascular cells, chondrocytes and fibroblasts. The approximately 70 kDa precursor protein (depending on isoform) is synthesized with an N-terminal 26-amino-acid signal peptide. This nascent polypeptide chain is transported into the lumen of the RER, where the signal peptide is removed cotranslationally [9]. 

SUGANO M, ISHIWAKI N, NAKASHIMA K (1984) Dietary protein-dependent modification of serum cholesterol level in rats significance of Arginine/lysine ratio. rinw Nutr Metab, 28 192-9. 

The rates are essentially independent of the distribution of metal in the MT with similar rates between Zn7—MTm (Cd, Zn)7-MT, and Cd7—MT. The values of the rate constants are ks = 6.9( 0.9) x 10 " s and kf=2.7( 1.2) x 10 s for the holo-protein. The slow rate constant is similar in magnitude to the first-order protein-dependent steps observed for reactions of DTNB (5,5 -dithiobis(2-nitrobenzoate)), EDTA (ethylenediamine tetraacetate), cisplatin, and other reagents, which has been attributed to a rearrangement of the protein. The fast step is more rapid by an order of magnitude, which suggests that other mechanisms are prevailing. 

Tanaka M., Treloar H., Kalb R.G., Greer C.A., et al. (1999). G(o) protein-dependent survival of primary accessory olfactory neurons. Proc Natl Acad Sci 96, 14106-14111. 

Amara A, Vidy A, Boulla G, et al. G protein-dependent CCR5 signaling is not required for efficient infection of primary T lymphocytes and macrophages by R5 human immunodeficiency vims type 1 isolates. J Virol 2003 77(4) 2550-2558. 

The addition of PVP 360,000 at a concentration of 0.75 g L 1 has been reported to yield a 35-fold increase in the level of extracellular foreign protein in suspended plant cell cultures [66]. The effectiveness of PVP in stabilizing secreted proteins depends on both the polymer molecular weight and its concentration. Low-molecular-weight (10,000 and 40,000) PVP was found to be less effective than PVP 360,000... 

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