Finally, in the examples of substrates not having phosphate groups present, GlcNAc, Glc and U, the binding of Mg+2 and Mn+2 to the substrates was so weak as to preclude accurate binding affinity determinations, which indicates the importance that the charged phosphates play in binding divalent metals.
To develop an in silico tool for identifying substrates of the yeast Ste20p kinase, our first step was to generate a learning set of positive and negative examples of substrates.
This is one of the most challenging examples of substrate and cofactor specificity that has not yet been fully elucidated.
Despite numerous structural reports, there have not been many examples of substrate-bound or product-bound structures (4– 9), making studies of mechanism and inhibition more difficult.
Numerous examples of substrate channeling have been reported, including DNA replication, RNA synthesis, purine and pyrimidine biosynthesis, protein biosynthesis, amino-acid metabolism, lipid metabolism, glycolysis, and the tricarboxylic acid cycle, etc. (10– 10).
The preparation of the two enantiomers of 2-methyl-3-aryl-propanols by fermentation of two regioisomers represents an interesting example of substrate-controlled enantioselective reaction.
The results provide an example of substrate effect in self-assemblies of functional molecules, which is significant for the design of molecular based devices.
A well-known example of substrate-dominated self-assembly is the epitaxial stripe nanopatterns formed by alkanes and alkane derivatives on highly oriented pyrolytic graphite (HOPG) [4 10].
In this view, Put2p would be an example of substrate recognition by conformational selection.
Transition metal surfaces (Cu, Ru, Pd, Pt, Pd/Zn, Pd/Pt), metal oxide surfaces (MgO, NiO) and supported d-metal particles (atoms, Pd nanosize clusters) are taken as examples of catalytic substrates.
Examples of such substrates include ICAD, the inactivation of which results in activation of the CAD endonuclease that contributes to apoptosis-associated DNA hydrolysis [36], [37].
