Spontaneous assembly

Bain C D, Troughton, E B Tao Y T, Evall J and Whitesides G M 1989 Formation of monolayer films by the spontaneous assembly of organic thiols from solution onto gold J. Am. Chem. Soc. Ill 321-35... 

SNARE motifs spontaneously assemble into SNARE complexes. These consist of a bundle of four intertwined a-helices that are connected by a total of 16 layers of mostly hydrophobic amino acid side chains. In the middle of the bundle, there is a highly conserved and polar 0-layer consisting of three glutamine and one arginine residue. These residues are among the most conserved in the SNARE superfamily and led to a classification of SNAREs into Q- and R-SNAREs, respectively. Different fusion steps require different sets of SNAREs but some SNAREs can participate in different complexes, and some fusion steps involve several SNARE complexes that appear to operate in parallel and independently. 

A particle that spontaneously assembles from viral coat proteins in the absence of other viral components. Vims-like particles (VLPs) generated from recombinant coat proteins are used in vaccines against hepatitis B vims and papillomavirus. 

Zhang SG, Holmes T, Lockshin C et al (1993) Spontaneous assembly of a self- complementary oligopeptide to form a stable macroscopic membrane. Proc Natl Acad Sci 90 3334—3338... 

Finally, to produce the structural and functional devices of the cell, polypeptides are synthesized by ribosomal translation of the mRNA. The supramolecular complex of the E. coli ribosome consists of 52 protein and three RNA molecules. The power of programmed molecular recognition is impressively demonstrated by the fact that aU of the individual 55 ribosomal building blocks spontaneously assemble to form the functional supramolecular complex by means of noncovalent interactions. The ribosome contains two subunits, the 308 subunit, with a molecular weight of about 930 kDa, and the 1590-kDa 50S subunit, forming particles of about 25-nm diameter. The resolution of the well-defined three-dimensional structure of the ribosome and the exact topographical constitution of its components are still under active investigation. Nevertheless, the localization of the multiple enzymatic domains, e.g., the peptidyl transferase, are well known, and thus the fundamental functions of the entire supramolecular machine is understood [24]. 

Myosin may be extracted via high-ionic-strength buffers and purified. Synthetic thick filaments of myosin spontaneously assemble upon lowering the ionic strength of its solution, exhibiting the morphological characteristics of native thick filaments. This process initiates with myosin monomers assembled into parallel dimers. The dimers assemble into antiparallel tetramers, the tetramers into octamers, and the octamers into minifilaments... 

Gabbai, F.P., Schier, A., Riede, J. and Tschrnkl, M.T. (1999) Micropore decoration with bidentate lewis adds spontaneous assembly of l,2-Bis(chloromercurio) tetrafluorobenzene. Angewandte Chemie International Edition, 38, 3547. 

An spontaneous assembly of 15 components is reported in the synthesis of [Ag9L6](OTf)9 where L is the hexadentate, tris-chelating 6,6-bis[2-(6-methylpyridine)]-3j3 -bipyrazine. The structure consists of a 3x3 grid of Ag-atoms (average Ag" Ag = 3.72(3)A), sandwiched between two almost perpendicular sets of three parallel L ligands (Figure 10).641... 

The iron storage protein ferritin is a small 20 kDa a-helical protein that spontaneously assembles into a hollow ball-like homo-24-mer. The outer diameter of the sphere is circa 12 nm and the inner diameter, or core diameter, is circa 8 nm. A smaller version, known as miniferritin or Dps protein (Dps = DNA protecting... 

Seifert JL, Connor RE, Kushon SA, Wang M, Armitage B (1999) Spontaneous assembly of helical cyanine dye aggregates on DNA nanotemplates. J Am Chem Soc 121 2987-2995... 

After elongation has proceeded for a sufficient period of time, the protomer and polymer will reach concentrations corresponding to the equilibrium constant Ko, which from our earlier discussion may be represented as k-/k+. This constant represents the critical concentration for polymer assembly, and protomer concentrations which fall below the magnitude of this constant will not spontaneously assemble. In this sec-... 

DNA has also been immobilized on Au electrode by its interaction with gem-ini surfactants [216]. Moreover, inclusion complexes of viologen-attached alkanethi-ols and a- and /J-cyclodextrins that spontaneously assemble on Au electrodes have been studied [217, 218]. 

The thermodynamic stability of the binuclear site has been demonstrated by the spontaneous assembly of [Fe20(02CR)2L2] (13) from ferric salts in the presence of water, an alkyl carboxylate salt, and a tridentate nitrogen donor ligand L that can cap an octahedral face on iron (8). Suitable ligands include tris(pyrazolyl)borates and 1,4,7-triazacyclononanes. Structure (13) is in essence a portion of the basic ferric acetate structure. The complexes are excellent physical and structural models of the diiron sites and model some aspects of reactivity including redox activity and interconversion of the oxo and hydroxo bridge. 

Biebuyck HA, Bain CD, Whitesides GM. Comparison of organic monolayers on polycrystalline gold spontaneously assembled from solutions containing dialkyl disulfides or alkanethiols. Langmuir 1994, 10, 1825-1831. 

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