Convergent functionality

Kemp s Acid Enzyme-Cleft and Self-Replication Models 347 5.2.1 Enzyme-Cleft Models with Convergent Functional Croups... 

Several key questions remain with regard to the regulation of tyrosine hydroxylase by phosphorylation. What is the precise effect of the phosphorylation of each of these serine residues on the catalytic activity of the enzyme How does the phosphorylation of multiple residues affect enzyme activity Does the phosphorylation of one residue affect the ability of the others to be phosphorylated Tyrosine hydroxylase provides a striking example as to how multiple intracellular messengers and protein kinases converge functionally through the phosphorylation of a single substrate protein. Phosphorylation of tyrosine hydroxylase by cAMP-dependent and Ca2+-dependent protein kinases and by MAPK cascades... 

The significance of convergent functional groups on the design of molecular receptors and clefts has been described (a) Rebek, J., Jr. ... 

The second term in this expression is evaluated in reciprocal space using Eq. (9.15) [Pg.197]

With K in the convergence function of Eq. (9.18) equal to 0.4 A-1, the accelerated convergence method reaches an accuracy of nine significant figures with inclusion of only 1000 unit cells. By comparison, about 50,000 unit cells would be required for a summation performed exclusively in direct space. 

Enzyme-Cleft Models with Convergent Functional Croups... 

J. Rebek, B. Askew, M. Killoran, D. Nemeth, F.T. Lin, Convergent Functional Groups 3. A Molecular Cleft Recognizes Substrates of Complementary Size, Shape, and Functionality , J. Am. Chem. Soc., 109, 2426 (1987)... 

Rebek, J., Jr., Duff, R. J., Gordon, W. E., and Parris, K. Convergent functional groups provide a measure of stereoelect ronic effects at carbonyl oxygen. J. Amer. Chem. Soc. 108, 6068-6069 (1986). 

Romano M, Claria J. Cyclooxygenase-2 and 5-lipoxygenase converging functions on cell proliferation and tumor angiogenesis implications for cancer therapy. EASEB J. 17 (2003) 1986-1995. 

Secant. The method uses a linear approximation of the Jacobian. It may be implemented with some enhancements, as half interval option. It is recommended for single variable, discontinuous or flat convergence functions. 

Conn, M.M. Deslongchamps, G. de Mendoza, J. Rebek, J.. Jr. Convergent functional groups. 13. High-affmity complexation of adenosine derivatives within induced binding pockets. J. Am. Chem. Soc. 1993,115 (9). 3548-3557. 

Molecular clefts that bear convergent functionality are of major interest. In systems of this type, a rigid spacer is used to create a scaffold onto which functional groups can be placed. These functional groups are often, but not always, directed toward each other but are held apart by the spacer. Guest binding takes place in the space between the functional groups, and selectivity is determined in part by the size of this aperture. 

Carcanague, D.R. Knobler, C.B. Diedrich. F. Water-soluble cyclophane receptors with convergent functional groups. J. Am. Chem. Soc. 1992. 114. 1515-1517. 

Askew. B.C. The design and synthesis of macrobicyclic 24. hosts featuring convergent functional groups. Tetrahedron... 

The generalization to functions of these operators may be as well proofed for analytical functions, i.e., for convergent functions though the series expansion. For instance, for coordinate operator analytical functions one may write that ... 

Key words. Recognition, hydrogen bonding, molecular clefts, convergent functionality, concerted catalysis, stereoelectronic effects. 

NEW MOLECULAR SHAPES FOR RECOGNITION AND CATALYSIS Convergent functionality... 

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