Self-assembling proteins

Development of methodologies for protein self-assembly into a predesigned three-dimensional protein lattice carries potential for the construction of protein scaffolds, offering potential applications such as platforms for the ordered positioning of other proteins via protein fusion or of organic molecules by specific binding. 

HBsAg was the first viral antigen to be produced in transgenic plants. The protein self-assembles into subviral mammalian particles of 22 nm, and is virtually indistinguishable from serum-derived and yeast-derived HBsAg in both infected sera as well as commercial vaccines with respect to size, density sedimentation, and immunogenicity. 

In principle, the expressions for pair potentials, osmotic pressure and second virial coefficients could be used as input parameters in computer simulations. The objective of performing such simulations is to clarify physical mechanisms and to provide a deeper insight into phenomena of interest, especially under those conditions where structural or thermodynamic parameters of the studied system cannot be accessed easily by experiment. The nature of the intermolecular forces responsible for protein self-assembly and phase behaviour under variation of solution conditions, including temperature, pH and ionic strength, has been explored using this kind of modelling approach (Dickinson and Krishna, 2001 Rosch and Errington, 2007 Blanch et al., 2002). 

Table 6.1 Theoretical estimation of the types of structures of protein self-assembly induced by interactions of food proteins (0.5 % w/v) with food-grade surfactants in aqueous solution (pH = 7.2, ionic strength = 0.05 M, 293 K) below the cmc (CITREM cmc = 15 mg/L SSL cmc = 3.5 mg/L PGE cmc = 1.0 mg/L (IFin el al., 2005)). See the text for definitions of k and k2.

When a protein is interacting with surfactant micelles, the following intrinsic features of the micelles are suggested as being of general importance in relation to their influence on the character of the protein self-assembly (IFin et al., 2005) ... 

Table 6.3 Effect of protein self-assembly, induced by interaction with lecithin, on the stability of foams stabilized by complexes of sodium caseinate (1 % w/v) with soy phospholipids Lipoid S-21 (1(T5 M) (Istarova et al., 2005 Semenova, 2007). Values of Mw and A 2 are presented for the protein with and without surfactant at three pH values. Also shown are photographs of foams recorded 9 minutes following foam preparation. In each of the images the volume of the glass vessel containing die foam is 10 ml. 

Kentsis, A., Borden, K.L.B. (2004). Physical mechanisms and biological significance of supramolecular protein self-assembly. Current Protein and Peptide Science, 5, 125-134. 

Kirnbauer R, Booy F, Cheng N, Lowy DR, Schiller JT (1992), Papillomavirus LI major capsid protein self-assembles into virus-like particles that are highly immunogenic, Proc. Natl Acad. Sci. USA 89 12180-12184. 

Virus-like particles (VLPs) (Noad and Roy 2003) are produced from viral capsid proteins. The capsid proteins self-assemble to form particles that resemble the virus from which the capsid proteins were derived, but lack any... 

Yang, A., Miron, S., Duchambon, P, Assam, L,. Blouquit, Y. and Craescu, C.T. (2006) The N-terminal domain of human centrin 2 has a closed stmcture, binds calcium with a very low affinity, and plays a role in the protein self-assembly. Biochemistry 45, 880-889. 

Kuznetsova N, Rau DC, Parsegian VA, Leikin S. Solvent hydrogen-bond network in protein self-assembly Solvation of collagen triple helices in nonaqueous solvents. Biophys. J. 1997 72 353-362. 

The addition of one more component (a cosolvent) to aqueous solutions of proteins can dramatically change the properties of those solutions, such as the protein solubility, protein self-assembling, and protein stabihty. Indeed, the solubility of proteins can be essentiahy changed by the addition of a third component.It is well known for a long time that the addition of certain compounds (such as urea) can cause protein denaturation, and that other cosolvents, such as glycerol, sucrose, etc., can stabilize at high concentrations the protein structure and preserve its enzymatic. .. . 1-6 activity. 

Key words Recombinant targeting proteins. Self-assembled protein complex. Targeted drug... 

Consultation of polyhedron models revealed the structure of 1 to conform to a snub cube, one of the 13 Archimedean solids, in which the vertices of the square faces correspond to the comers of 2 and the centroids of the eight triangles that adjoin three squares correspond to the eight water molecules. Indeed, to us, the ability of six resorcin[4]arenes to self-assemble to form 1 was reminiscent of spherical viruses in which identical copies of proteins self-assemble, by way of noncovalent forces, to form viral capsids having icosahedral symmetry and a shell-like enclosure. In fact, owing to the fit displayed by its components, 1 exhibits a topology that agrees with the theory of vims shell stmcture which states that... 

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