Proteins with Small Molecules

7 INTERACTOMES AND THE COMPLEXITY OF ORGANISMS IT IS THE NUMBER OF INTERACTOMES THAT MATTERS IN UNDERSTANDING THE COMPLEXITY OF AN ORGANISM AND NOT THE NUMBER OF GENES 

Protein-protein interactions control the cellular function and structure in every organism. Most often, certain small molecules interact with proteins 

Chaurasia, G. et al. 2009. UniHI 4 new tools for query, analysis and visualization of the human protein-protein interactome. Nucleic Acids Res. 37, D657-D660. 

Fields, S., and O. K. Song. 1989. A novel genetic system to detect protein-protein interactions. Nature 340, 245-246. 

Idekar, T., V. Thorsson, J. A. Ranish, R. Christmas, J. Buhler, J. M. Eng, R. Bumgarner, D. R. Goodlett, R. Abersold, and L. Hood. 2001. Integrated genomic and proteomic analyses of a systematically perturbed metabolic network. Science 292, 929-933. 

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The PDB contains 20 254 experimentally determined 3D structures (November, 2002) of macromolecules (nucleic adds, proteins, and viruses). In addition, it contains data on complexes of proteins with small-molecule ligands. Besides information on the structure, e.g., sequence details (primary and secondary structure information, etc.), atomic coordinates, crystallization conditions, structure factors. 

Here too we have an example of the rate at which scientific information is created currently. The earliest three-dimensional protein structures were products of decades of work. In the succeeding four decades, we have defined three-dimensional stractures for more than 5000 proteins and complexes of proteins with small molecules. They occupy huge publicly available databases. They grow daily. This information is of great importance for several purposes. Among these is the design of novel molecules useful in human clinical medicine. 

A general method for the covalent labeling of fusion proteins with small molecules In Vivo Nat Biotechnol2, 86-89. 

Labeling of Fusion Proteins with Small Molecules in vivo... 

Yin J, Liu F, Li X, Walsh CT. Labeling proteins with small molecules by site-specific posttranslational modification. J. Am. Chem. Soc. 2004 126 7754-7755. 

It is clear from the discussion of metal homeostasis that the fuU characterization of a protein requires not only its study in the isolated form but also the investigation of its relevant interactions. Therefore, the interactions of metal-binding proteins with small molecules and other proteins are an obvious perspective in biological inorganic research. This implies the importance of the identification and structure characterization of weak protein-protein complexes that represent the key steps of the biochemical processes discussed here. Moreover, metal-mediated protein-protein interactions are just beginning to be identified and will become an important field of research. 

I. Chen, A. Ting, Site-specific labeling of proteins with small molecules in live cells, Curr. Opin. Biotechnol. 2005, 16, 35-40. 

Fig. 14.2-3 Gene Family distribution of nonredundant human proteins with small-molecule chemical leads with binding affinities <10 pM. Data derived from an analysis of Inpharmatica s StARLITe database.

For a foam to be stable, once formed, some change must occur in the surface-active molecules within the film. Such changes could be brought about either by changes in the conformation of the protein or by cross-linking of the protein with small molecules such as the iso-a-acids or by metal ions [138]. Oxidation is not thought to be important in the time concerned in foam formation. On the other hand it has been pointed out that, at the... 

Vn. Reversible Combination of Sebum Albumin and Other Plasma Proteins with Small Molecules or Ions ... 

KEP 03] Keppler A., GENDREizig S., Gronemeyer T. et al, A general method for the covalent labeling of fusion proteins with small molecules in vivo . Nature Biotechnology, vol. 21, pp. 86-89, 2003. 

SITE-SPECIFIC LABELING OF PROTEINS WITH SMALL MOLECULES FOR IMAGING... 

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