This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1k3m
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:1k3m.gif|left|200px]] | [[Image:1k3m.gif|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_1k3m", creates the "Structure Box" on the page. | |
| - | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
| - | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
| - | | | + | or leave the SCENE parameter empty for the default display. |
| - | | | + | --> |
| - | + | {{STRUCTURE_1k3m| PDB=1k3m | SCENE= }} | |
| - | + | ||
| - | + | ||
| - | }} | + | |
'''NMR STRUCTURE OF HUMAN INSULIN MUTANT ILE-A2-ALA, HIS-B10-ASP, PRO-B28-LYS, LYS-B29-PRO, 15 STRUCTURES''' | '''NMR STRUCTURE OF HUMAN INSULIN MUTANT ILE-A2-ALA, HIS-B10-ASP, PRO-B28-LYS, LYS-B29-PRO, 15 STRUCTURES''' | ||
| Line 19: | Line 16: | ||
==About this Structure== | ==About this Structure== | ||
| - | 1K3M is a [[Protein complex]] structure | + | 1K3M is a [[Protein complex]] structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1K3M OCA]. |
==Reference== | ==Reference== | ||
| Line 31: | Line 28: | ||
[[Category: Weiss, M A.]] | [[Category: Weiss, M A.]] | ||
[[Category: Xu, B.]] | [[Category: Xu, B.]] | ||
| - | [[Category: | + | [[Category: Hormone]] |
| - | [[Category: | + | [[Category: Human insulin]] |
| - | [[Category: | + | [[Category: Mutant]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 22:15:43 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 19:15, 2 May 2008
NMR STRUCTURE OF HUMAN INSULIN MUTANT ILE-A2-ALA, HIS-B10-ASP, PRO-B28-LYS, LYS-B29-PRO, 15 STRUCTURES
Overview
To investigate the cooperativity of insulin's structure, a cavity-forming substitution was introduced within the hydrophobic core of an engineered monomer. The substitution, Ile(A2)-->Ala in the A1-A8 alpha-helix, does not impair disulfide pairing between chains. In accord with past studies of cavity-forming mutations in globular proteins, a decrement was observed in thermodynamic stability (DeltaDeltaG(u) 0.4-1.2 kcal/mole). Unexpectedly, CD studies indicate an attenuated alpha-helix content, which is assigned by NMR spectroscopy to selective destabilization of the A1-A8 segment. The analog's solution structure is otherwise similar to that of native insulin, including the B chain's supersecondary structure and a major portion of the hydrophobic core. Our results show that (1) a cavity-forming mutation in a globular protein can lead to segmental unfolding, (2) tertiary packing of Ile(A2), a residue of low helical propensity, stabilizes the A1-A8 alpha-helix, and (3) folding of this segment is not required for native disulfide pairing or overall structure. We discuss these results in relation to a hierarchical pathway of protein folding and misfolding. The Ala(A2) analog's low biological activity (0.5% relative to the parent monomer) highlights the importance of the A1-A8 alpha-helix in receptor recognition.
About this Structure
1K3M is a Protein complex structure. Full crystallographic information is available from OCA.
Reference
A cavity-forming mutation in insulin induces segmental unfolding of a surrounding alpha-helix., Xu B, Hua QX, Nakagawa SH, Jia W, Chu YC, Katsoyannis PG, Weiss MA, Protein Sci. 2002 Jan;11(1):104-16. PMID:11742127 Page seeded by OCA on Fri May 2 22:15:43 2008
Categories: Protein complex | Chu, Y C. | Hua, Q X. | Jia, W. | Katsoyannis, P G. | Nakagawa, S H. | Weiss, M A. | Xu, B. | Hormone | Human insulin | Mutant
