Conantokin

Complexes, see also specific type in solution, structures, see X-ray diffraction n-Complexes, 4 178-184 Complex formation constant, outersphere, 43 46, 55 electrovalent interaction in, 3 269-270 Compressibility coefficient of activation, 42 9 Comproportionation constants, class II mixed-valence complexes, 41 290-292 Comproportionation equilibrium, 41 280-281 Compton effect, 3 172 Conantokins, calcium binding, 46 470-471 Concanavalin A, 36 61, 46 308 Concensus motif, 47 451 Concentration-proportional titrations of poly-metalates, 19 250, 251, 254 Condensation... 

Conantokins Conantokin-T GE77YQKML7NLR7AQVKKNA Conus tulipa p receptor NMDA receptor... 

Conantokins bind to the V-methyl-D-aspartate (NMDA) receptor, one form of ionotropic glutamate receptor. The therapeutic potential of clinically available NMDA receptor antagonists is currently limited because of the prevalence of undesirable side effects, thought to be a result of a lack of specificity. 

Conantokin-G (Con-G), a 17-residue linear conopeptide that contains five 7-carboxyglutamate (Gla) residues, is an antagonist of the NMDA receptor. Conantokin-G has been shown to be an effective antiepileptic agent in several animal models of seizure. ... 

We are aware that several important calcium-binding proteins have been neglected and that our selection of proteins is clearly biased by our own particular interests. We have also included some odd proteins such as conantokins and neglected more important ones such as phospholipase A2. 

Cone snails produce biologically active peptides to paralyze their prey. The peptides are known as conotoxins (176-178). Most of them are small and stabilized by disulfide bonds. Two unusual members of the conotoxin family are conantokin G from Conus geographica (179) and conantokin T from Conus tulipa (180), which lack disulfide bonds but are rich in y-carboxyglutamic acid residues ... 

The role of the Gla residues is not yet fully understood, but a synthetic conantokin peptide with Glu instead of Gla has been shown to be inactive. However, it is still not clear whether Ca2+ is essential for biological functioning of the conantokin peptides (181, 182). There appears to be no thorough study of the calcium ion binding to these peptides, though CD spectroscopy has been used to study the change in helical content as a function of calcium concentration (183). The... 

Donevan, S.D. and McCabe, R.T. (2000) Conantokin G is an NR2B-selective competitive antagonist of N-methyl-o-aspartate receptors. Mol. Pharmacol, 58, 614-623. 

Gowd, KH., Twede, V., Watkins, M., Krishnan, KS., Teichert, R.W., Bulaj, G., and Olivera, B.M. (2008) Conantokin-P, an unusual conantokin with a long disulfide loop. Toxicon, 52, 203-213. 

Haack, J.A., Rivier, J., Parks, T.N., Mena, E.E., Cruz, L.J., and Olivera, B.M. (1990) Conantokin-T a y-carboxyglutamate containing peptide with N-methyl-D-aspartate antagonist activity. J. Biol. Chem., 265, 6025-6029. 

Jimenez, E.C. (2009) Conantokins from sleeper activity to dmg development. Philipp. Sci. Lett., 2,60-66. 

Klein, R,C Galdzicki, Z., and CasteHino, F,J, (1999) Inhibition of NMDA-induced currents by conantokin-G and conantokin-T in... 

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