Hook protein

Silva-Herzog, E. and Dreyfus, G. (1999). Interaction of Fhl, a component of the flagellar export apparatus, with flagellin and hook protein. Biochim. Biophys. Acta 1431, 374-383. 

Kelly BL, Singh G, Alyar A. Molecular and cellular eharacterization of an AT-hook protein from Leishmania. PLoS One. 201 l 6(6) e21412. doi 10.1371/joumal.pone. 00214112. 

Flagellar hook protein Salmonella SJ25 208 -9 600 Tris, pFl 8.2 microbiuret 76K1... 

The experiments described above indicate that technology is available to couple SPR with mass spectrometry. These methods should be useful for protein-protein interaction mapping. For example, immobilized proteins can be used as hooks for fishing binding partners from complex protein mixtures under native conditions. The coupling of techniques can lead not only to the rapid identification of interacting proteins but will also provide information on the kinetic parameters of the interaction. This approach should serve as an excellent complement to the use of in vivo techniques such as the yeast two-hybrid system. 

In normal cells, the GDP/GTP-binding proteins, after protein synthesis, move to the cell membrane to which they become hooked by a hydrophobic farnesyl group. The y-subunit is anchored in the membrane by a post-translational modification of the C-terminal CAAX sequence (C - cystein, AA - aliphatic amino acids, X - methionine). This protein is first enzymatically farnesylated by a specific farnesyltransferase, then the AAX part is cleaved by specific proteases and finally the cystein residue is converted to a methyl ester. 

Cojocel, C., Dociu, N., Maita, K., Sleight, S.D. and Hook, J.B. (1983). Effects of aminoglycosides on glomerular permeability, tubular reabsorption, and intracellular catabolism of the cationic low molecular weight protein lysozyme. Toxicol. Appl. Pharm. 39 129-139. 

Schwarz-Linek, U., Hook, M., and Potts, J. R. (2006). Fibronectin-binding proteins of grampositive cocci. Microbes Infect. 8, 2291-2298. 

Speziale, P., Hook, M., Wadstrom, T., and Timpl, R. (1982). Binding of basement membrane protein laminin to Escherichia coli. FEBS Lett. 175, 55-58. 

Now we have the structures of the 20 amino acids that constitute proteins. So the next question is how these get linked together to form the polymer. The answer is that they hook together by joining the amino group of one amino acid to the carboxyl group of another with the elimination of water ... 

So far, we know the structures of the 20 amino acids that appear in proteins and how they are hooked together. We also know that there is an enormous number of possible proteins. 

An exotic function of glycoproteins is to act as antifreezes. Specifically, a number of Antarctic fish live in water cooled to about -1.9°C, a temperature below the freezing point of water and below that where the blood, mostly water, of these fish is expected to freeze. Clearly, this would be a disaster for these fish. They are saved from this fate by antifreeze glycoproteins. These proteins contain about 50 repeats of the tripeptide Ala-Ala-Thr. To each of these threonine residues is hooked a specific disaccharide. 

Fig. 1. Schematic diagrams based on the solution NMR structure of a complex of the second AT-hook motif of the human HMGAla protein bound to the minor groove of an AT-rich synthetic duplex DNA fragment [25], Various projected views of either the AT-hook peptide, or a co-complex of the peptide with DNA are shown (see text for details). Modified from Ref. [7].

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