|
|
| Line 1: |
Line 1: |
| [[Image:1t9e.gif|left|200px]] | | {{Seed}} |
| | [[Image:1t9e.png|left|200px]] |
|
| |
|
| <!-- | | <!-- |
| Line 9: |
Line 10: |
| {{STRUCTURE_1t9e| PDB=1t9e | SCENE= }} | | {{STRUCTURE_1t9e| PDB=1t9e | SCENE= }} |
|
| |
|
| '''NMR solution structure of a disulfide analogue of the cyclic sunflower trypsin inhibitor SFTI-1'''
| | ===NMR solution structure of a disulfide analogue of the cyclic sunflower trypsin inhibitor SFTI-1=== |
|
| |
|
|
| |
|
| ==Overview==
| | <!-- |
| SFTI-1 is a novel 14 amino acid peptide comprised of a circular backbone constrained by three proline residues, a hydrogen-bond network, and a single disulfide bond. It is the smallest and most potent known Bowman-Birk trypsin inhibitor and the only one with a cyclic peptidic backbone. The solution structure of [ABA(3,11)]SFTI-1, a disulfide-deficient analogue of SFTI-1, has been determined by (1)H NMR spectroscopy. The lowest energy structures of native SFTI-1 and [ABA(3,11)]SFTI-1 are similar and superimpose with a root-mean-square deviation over the backbone and heavy atoms of 0.26 +/- 0.09 and 1.10 +/- 0.22 A, respectively. The disulfide bridge in SFTI-1 was found to be a minor determinant for the overall structure, but its removal resulted in a slightly weakened hydrogen-bonding network. To further investigate the role of the disulfide bridge, NMR chemical shifts for the backbone H(alpha) protons of two disulfide-deficient linear analogues of SFTI-1, [ABA(3,11)]SFTI-1[6,5] and [ABA(3,11)]SFTI-1[1,14] were measured. These correspond to analogues of the cleavage product of SFTI-1 and a putative biosynthetic precursor, respectively. In contrast with the cyclic peptide, it was found that the disulfide bridge is essential for maintaining the structure of these open-chain analogues. Overall, the hydrogen-bond network appears to be a crucial determinant of the structure of SFTI-1 analogues.
| | The line below this paragraph, {{ABSTRACT_PUBMED_15667208}}, adds the Publication Abstract to the page |
| | (as it appears on PubMed at http://www.pubmed.gov), where 15667208 is the PubMed ID number. |
| | --> |
| | {{ABSTRACT_PUBMED_15667208}} |
|
| |
|
| ==About this Structure== | | ==About this Structure== |
| 1T9E is a [[Single protein]] structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1T9E OCA]. | | 1T9E is a [[Single protein]] structure. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1T9E OCA]. |
|
| |
|
| ==Reference== | | ==Reference== |
| Line 27: |
Line 31: |
| [[Category: Nmr]] | | [[Category: Nmr]] |
| [[Category: Sunflower trypsin inhibitor]] | | [[Category: Sunflower trypsin inhibitor]] |
| ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 09:42:09 2008'' | | |
| | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 29 10:12:06 2008'' |
