Receptors, phage

Scarselli E, Esposito G, Traboni C, Receptor phage. Display of functional domains of the human high affinity IgE receptor on the Ml3 phage surface, FEBS Lett., 329 223-226, 1993. 

Figure 10. Diagrammatic sketch of the competition between phage colicin and siderophore for the outer membrane receptor in the enteric bacteria. (A) Escherichia coli K-12. (1) Ferrichrome receptor phage = TI, T5, 80 colicin = M siderophore = ferrichrome. (2) Ferric en-terobactin receptor phage = colicin = B siderophore = ferric entero-bactin. (B) Salmonella typhimurium LT-2. (1) Ferrichrome receptor ...

White, S. J., Simmonds, R. E., Lane, D. A., Baker, A. H. (2005). Efficient isolation of peptide ligands for the endothelial cell protein C receptor (EPCR) using candidate receptor phage display biopanning. Peptides, 26, 1264-1269. 

Phage display of random peptide libraries identified agonists of erythropoietin receptor... 

Protein engineering is now routinely used to modify protein molecules either via site-directed mutagenesis or by combinatorial methods. Factors that are Important for the stability of proteins have been studied, such as stabilization of a helices and reducing the number of conformations in the unfolded state. Combinatorial methods produce a large number of random mutants from which those with the desired properties are selected in vitro using phage display. Specific enzyme inhibitors, increased enzymatic activity and agonists of receptor molecules are examples of successful use of this method. 

Jacobsson, K., and Frykberg, L. (1995). Cloning of ligand-binding domains of bacterial receptors by phage display. BioTechniques 18, 878-885. 

Sche, P. P., McKenzie, K. M., White, J. D., and Austin, D. J. (1999). Display cloning functional identification of natural product receptors using cDNA-phage display. Chem. Biol. 6, 707-716. 

In general, virus receptors carry out normal functions in the cell. For example, in bacteria some phage receptors are pili or flagella, others are cell-envelope components, and others are transport binding proteins. The receptor for influenza vims is a glycoprotein found on red blood cells and on cells of the mucous membrane of susceptible animals, whereas the receptor site of poliovirus is a lipoprotein. However, many animal and plant viruses do not have specific attachment sites at all and the vims enters passively as a result of phagocytosis or some other endocytotic process. 

Host-range mutations are those that change the range of hosts that the virus can infect. Host resistance to phage infection can be due to an alteration in receptor sites on the surface of the host cell, so that the virus can no longer attach, and host-range mutations of... 

Mainly the outer membrane ferrichrome receptor and transporter FhuA will be discussed because most structural and functional studies have been performed with this protein. In fact, FhuA was the first outer membrane protein identified (called TonA), with known functions as a phage and colicin receptor, that are related to iron transport (for a historical account, see Braun and Hantke 1977). 

Rajotte D, Ruoslahti E. Membrane dipeptidase is the receptor for a lung-targeting peptide identified by in vivo phage display. J Biol Chem 1999 274 11593-11598. 

Steinbacher, S., Baxa, U., Miller, S., Weintraub, A., Seckler, R., and Huber, R. (1996). Crystal structure of phage P22 tailspike protein complexed with Salmonella sp. O-antigen receptors. Proc. Natl. Acad. Sci. USA 93, 10584-10588. 

Luckey, M. and Nikaido, H. (1980). Specificity of diffusion channels produced by lambda phage receptor protein of Escherichia coli, Proc. Natl Acad. Sci. USA, 11, 167-171. 

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