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.
2jpj
From Proteopedia
(New page: 200px<br /><applet load="2jpj" size="350" color="white" frame="true" align="right" spinBox="true" caption="2jpj" /> '''Lactococcin G-a in DPC'''<br /> ==Overview=...) |
|||
| Line 22: | Line 22: | ||
[[Category: peptide]] | [[Category: peptide]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri Mar 14 09:42:49 2008'' |
Revision as of 07:42, 14 March 2008
|
Lactococcin G-a in DPC
Overview
The three-dimensional structures of the two peptides, lactococcin G-alpha (LcnG-alpha; contains 39 residues) and lactococcin G-beta (LcnG-beta, contains 35 residues), that constitute the two-peptide bacteriocin lactococcin G (LcnG) have been determined by nuclear magnetic resonance (NMR) spectroscopy in the presence of DPC micelles and TFE. In DPC, LcnG-alpha has an N-terminal alpha-helix (residues 3-21) that contains a GxxxG helix-helix interaction motif (residues 7-11) and a less well defined C-terminal alpha-helix (residues 24-34), and in between (residues 18-22) there is a second somewhat flexible GxxxG-motif. Its structure in TFE was similar. In DPC, LcnG-beta has an N-terminal alpha-helix (residues 6-19). The region from residues 20 to 35, which also contains a flexible GxxxG-motif (residues 18-22), appeared to be fairly unstructured in DPC. In the presence of TFE, however, the region between and including residues 23 and 32 formed a well defined alpha-helix. The N-terminal helix between and including residues 6 and 19 seen in the presence of DPC, was broken at residues 8 and 9 in the presence of TFE. The N-terminal helices, both in LcnG-alpha and -beta, are amphiphilic. We postulate that LcnG-alpha and -beta have a parallel orientation and interact through helix-helix interactions involving the first GxxxG (residues 7-11) motif in LcnG-alpha and the one (residues 18-22) in LcnG-beta, and that they thus lie in a staggered fashion relative to each other.
About this Structure
2JPJ is a Single protein structure of sequence from Lactococcus lactis. Full crystallographic information is available from OCA.
Reference
Three-dimensional structure of the two peptides that constitute the two-peptide bacteriocin lactococcin G., Rogne P, Fimland G, Nissen-Meyer J, Kristiansen PE, Biochim Biophys Acta. 2007 Dec 15;. PMID:18187052
Page seeded by OCA on Fri Mar 14 09:42:49 2008
