3leu
From Proteopedia
(New page: 200px<br /><applet load="3leu" size="450" color="white" frame="true" align="right" spinBox="true" caption="3leu" /> '''HIGH RESOLUTION 1H NMR STUDY OF LEUCOCIN A I...) |
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| - | [[Image:3leu.jpg|left|200px]]<br /><applet load="3leu" size=" | + | [[Image:3leu.jpg|left|200px]]<br /><applet load="3leu" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="3leu" /> | caption="3leu" /> | ||
'''HIGH RESOLUTION 1H NMR STUDY OF LEUCOCIN A IN DODECYLPHOSPHOCHOLINE MICELLES, 19 STRUCTURES (1:40 RATIO OF LEUCOCIN A:DPC) (0.1% TFA)'''<br /> | '''HIGH RESOLUTION 1H NMR STUDY OF LEUCOCIN A IN DODECYLPHOSPHOCHOLINE MICELLES, 19 STRUCTURES (1:40 RATIO OF LEUCOCIN A:DPC) (0.1% TFA)'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The first three-dimensional structure of a type IIa bacteriocin from | + | The first three-dimensional structure of a type IIa bacteriocin from lactic acid bacteria is reported. Complete 1H resonance assignments of leucocin A, a 37 amino acid antimicrobial peptide isolated from the lactic acid bacterium Leuconostoc gelidum UAL187, were determined in 90% trifluoroethanol (TFE)-water and in aqueous dodecylphosphocholine (DPC) micelles (1:40 ratio of leucocin A:DPC) using two-dimensional NMR techniques (e.g., DQF-COSY, TOCSY, NOESY). Circular dichroism spectra, NMR chemical shift indices, amide hydrogen exchange rates, and long-range nuclear Overhauser effects indicate that leucocin A adopts a reasonably well defined structure in both TFE and DPC micelle environments but exists as a random coil in water or aqueous DMSO. Distance geometry and simulated annealing calculations were employed to generate structures for leucocin A in both lipophilic media. While some differences were noted between the structures calculated for the two different solvent systems, in both, the region encompassing residues 17-31 assumes an essentially identical amphiphilic alpha-helix conformation. A three-strand antiparallel beta-sheet domain (residues 2-16), anchored by the disulfide bridge, is also observed in both media. In TFE, these two regions have a more defined relationship relative to each other, while, in DPC micelles, the C-terminus is folded back onto the alpha-helix. The implications of these structural features with regard to the antimicrobial mechanism of action and target recognition are discussed. |
==About this Structure== | ==About this Structure== | ||
| - | 3LEU is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Leuconostoc_gelidum Leuconostoc gelidum]. Full crystallographic information is available from [http:// | + | 3LEU is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Leuconostoc_gelidum Leuconostoc gelidum]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3LEU OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Leuconostoc gelidum]] | [[Category: Leuconostoc gelidum]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Gallagher, N | + | [[Category: Gallagher, N L.F.]] |
| - | [[Category: Nakashima, T | + | [[Category: Nakashima, T T.]] |
| - | [[Category: Niemczura, W | + | [[Category: Niemczura, W P.]] |
[[Category: Sailer, M.]] | [[Category: Sailer, M.]] | ||
| - | [[Category: Stiles, M | + | [[Category: Stiles, M E.]] |
| - | [[Category: Vederas, J | + | [[Category: Vederas, J C.]] |
[[Category: antibacterial peptide]] | [[Category: antibacterial peptide]] | ||
[[Category: bacteriocin]] | [[Category: bacteriocin]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 19:10:01 2008'' |
Revision as of 17:10, 21 February 2008
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HIGH RESOLUTION 1H NMR STUDY OF LEUCOCIN A IN DODECYLPHOSPHOCHOLINE MICELLES, 19 STRUCTURES (1:40 RATIO OF LEUCOCIN A:DPC) (0.1% TFA)
Overview
The first three-dimensional structure of a type IIa bacteriocin from lactic acid bacteria is reported. Complete 1H resonance assignments of leucocin A, a 37 amino acid antimicrobial peptide isolated from the lactic acid bacterium Leuconostoc gelidum UAL187, were determined in 90% trifluoroethanol (TFE)-water and in aqueous dodecylphosphocholine (DPC) micelles (1:40 ratio of leucocin A:DPC) using two-dimensional NMR techniques (e.g., DQF-COSY, TOCSY, NOESY). Circular dichroism spectra, NMR chemical shift indices, amide hydrogen exchange rates, and long-range nuclear Overhauser effects indicate that leucocin A adopts a reasonably well defined structure in both TFE and DPC micelle environments but exists as a random coil in water or aqueous DMSO. Distance geometry and simulated annealing calculations were employed to generate structures for leucocin A in both lipophilic media. While some differences were noted between the structures calculated for the two different solvent systems, in both, the region encompassing residues 17-31 assumes an essentially identical amphiphilic alpha-helix conformation. A three-strand antiparallel beta-sheet domain (residues 2-16), anchored by the disulfide bridge, is also observed in both media. In TFE, these two regions have a more defined relationship relative to each other, while, in DPC micelles, the C-terminus is folded back onto the alpha-helix. The implications of these structural features with regard to the antimicrobial mechanism of action and target recognition are discussed.
About this Structure
3LEU is a Single protein structure of sequence from Leuconostoc gelidum. Full crystallographic information is available from OCA.
Reference
Three-dimensional structure of leucocin A in trifluoroethanol and dodecylphosphocholine micelles: spatial location of residues critical for biological activity in type IIa bacteriocins from lactic acid bacteria., Fregeau Gallagher NL, Sailer M, Niemczura WP, Nakashima TT, Stiles ME, Vederas JC, Biochemistry. 1997 Dec 9;36(49):15062-72. PMID:9398233
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