1gur: Difference between revisions
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< | ==GURMARIN, A SWEET TASTE-SUPPRESSING POLYPEPTIDE, NMR, 10 STRUCTURES== | ||
<StructureSection load='1gur' size='340' side='right'caption='[[1gur]]' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1gur]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Gymnema_sylvestre Gymnema sylvestre]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GUR OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1GUR FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR, 10 models</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PCA:PYROGLUTAMIC+ACID'>PCA</scene></td></tr> | |||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1gur FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1gur OCA], [https://pdbe.org/1gur PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1gur RCSB], [https://www.ebi.ac.uk/pdbsum/1gur PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1gur ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/GUR_GYMSY GUR_GYMSY] Suppresses strongly the sweet taste responses in the rat with high specificity to sucrose, glucose, glycine, and saccharin. This effect is reversible, but complete recovery of the suppressed responses required at least 3h. Gurmarin showed no effect or only a very weak effect on the sweet taste sensation in humans. | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The solution structure of gurmarin was studied by two-dimensional proton NMR spectroscopy at 600 MHz. Gurmarin, a 35-amino acid residue polypeptide recently discovered in an Indian-originated tree Gymnema sylvestre, selectively suppresses the neural responses of rat to sweet taste stimuli. Sequence-specific resonance assignments were obtained for all backbone protons and for most of the side-chain protons. The three-dimensional solution structure was determined by simulated-annealing calculations on the basis of 135 interproton distance constraints derived from NOEs, six distance constraints for three hydrogen bonds and 16 dihedral angle constraints derived from coupling constants. A total of 10 structures folded into a well-defined structure with a triple-stranded antiparallel beta-sheet. The average rmsd values between any two structures were 1.65 +/- 0.39 A for the backbone atoms (N, C alpha, C) and 2.95 +/- 0.27 A for all heavy atoms. The positions of the three disulfide bridges, which could not be determined chemically, were estimated to be Cys3-Cys18, Cys10-Cys23 and Cys17-Cys33 on the basis of the NMR distance constraints. This disulfide bridge pattern in gurmarin turned out to be analogous to that in omega-conotoxin and Momordica charantia trypsin inhibitor-II, and the topology of folding was the same as that in omega-conotoxin. | |||
Three-dimensional structure of gurmarin, a sweet taste-suppressing polypeptide.,Arai K, Ishima R, Morikawa S, Miyasaka A, Imoto T, Yoshimura S, Aimoto S, Akasaka K J Biomol NMR. 1995 Apr;5(3):297-305. PMID:7787425<ref>PMID:7787425</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 1gur" style="background-color:#fffaf0;"></div> | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
== | |||
== | |||
[[Category: Gymnema sylvestre]] | [[Category: Gymnema sylvestre]] | ||
[[Category: | [[Category: Large Structures]] | ||
[[Category: Aimoto | [[Category: Aimoto S]] | ||
[[Category: Akasaka | [[Category: Akasaka K]] | ||
[[Category: Arai | [[Category: Arai K]] | ||
[[Category: Imoto | [[Category: Imoto T]] | ||
[[Category: Ishima | [[Category: Ishima R]] | ||
[[Category: Morikawa | [[Category: Morikawa S]] | ||
[[Category: Yoshimura | [[Category: Yoshimura S]] | ||
Latest revision as of 10:23, 23 October 2024
GURMARIN, A SWEET TASTE-SUPPRESSING POLYPEPTIDE, NMR, 10 STRUCTURESGURMARIN, A SWEET TASTE-SUPPRESSING POLYPEPTIDE, NMR, 10 STRUCTURES
Structural highlights
FunctionGUR_GYMSY Suppresses strongly the sweet taste responses in the rat with high specificity to sucrose, glucose, glycine, and saccharin. This effect is reversible, but complete recovery of the suppressed responses required at least 3h. Gurmarin showed no effect or only a very weak effect on the sweet taste sensation in humans. Publication Abstract from PubMedThe solution structure of gurmarin was studied by two-dimensional proton NMR spectroscopy at 600 MHz. Gurmarin, a 35-amino acid residue polypeptide recently discovered in an Indian-originated tree Gymnema sylvestre, selectively suppresses the neural responses of rat to sweet taste stimuli. Sequence-specific resonance assignments were obtained for all backbone protons and for most of the side-chain protons. The three-dimensional solution structure was determined by simulated-annealing calculations on the basis of 135 interproton distance constraints derived from NOEs, six distance constraints for three hydrogen bonds and 16 dihedral angle constraints derived from coupling constants. A total of 10 structures folded into a well-defined structure with a triple-stranded antiparallel beta-sheet. The average rmsd values between any two structures were 1.65 +/- 0.39 A for the backbone atoms (N, C alpha, C) and 2.95 +/- 0.27 A for all heavy atoms. The positions of the three disulfide bridges, which could not be determined chemically, were estimated to be Cys3-Cys18, Cys10-Cys23 and Cys17-Cys33 on the basis of the NMR distance constraints. This disulfide bridge pattern in gurmarin turned out to be analogous to that in omega-conotoxin and Momordica charantia trypsin inhibitor-II, and the topology of folding was the same as that in omega-conotoxin. Three-dimensional structure of gurmarin, a sweet taste-suppressing polypeptide.,Arai K, Ishima R, Morikawa S, Miyasaka A, Imoto T, Yoshimura S, Aimoto S, Akasaka K J Biomol NMR. 1995 Apr;5(3):297-305. PMID:7787425[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References |
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