1w5u
From Proteopedia
| Line 4: | Line 4: | ||
==Overview== | ==Overview== | ||
| - | Gramicidin D (gD) is a naturally occurring ionophoric antibiotic that | + | Gramicidin D (gD) is a naturally occurring ionophoric antibiotic that forms membrane channels specific for monovalent cations. The crystal structure of the RbCl complex of gD has been determined at 1.14 A resolution from low-temperature (100 K) synchrotron-radiation data with a final R of 16%. The structure was refined with anisotropic temperature factors for all non-H atoms and with partial occupancies for many of them. The asymmetric unit in the crystal contains four crystallographically independent molecules that form two right-handed antiparallel double-stranded dimers. There are seven distinct rubidium-binding sites in each dimeric channel. The occupancy factors of Rb cations are between 0.11 and 0.35 and the total ion contents of the two crystallographically independent channels are 1.59 and 1.22 ions, respectively. Although each channel is 'chemically symmetrical', the side-chain conformations, the distributions of rubidium cations and their binding sites in the two independent channels are not. Cations are 'coordinated' by delocalized pi-electrons of three to five carbonyl groups that together with peptide backbone chains form the gramicidin channel walls. The water:cation ratio in the channel interior is four or five:one, and five or six waters separate Rb cations during their passage through the channel. |
==About this Structure== | ==About this Structure== | ||
| Line 14: | Line 14: | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Bojarska, J.]] | [[Category: Bojarska, J.]] | ||
| - | [[Category: Burkhart, B | + | [[Category: Burkhart, B M.]] |
| - | [[Category: Duax, W | + | [[Category: Duax, W L.]] |
| - | [[Category: Glowka, M | + | [[Category: Glowka, M L.]] |
| - | [[Category: Langs, D | + | [[Category: Langs, D A.]] |
[[Category: Olczak, A.]] | [[Category: Olczak, A.]] | ||
| - | [[Category: Pangborn, W | + | [[Category: Pangborn, W A.]] |
[[Category: Szczesio, M.]] | [[Category: Szczesio, M.]] | ||
[[Category: Wawrzak, Z.]] | [[Category: Wawrzak, Z.]] | ||
| Line 31: | Line 31: | ||
[[Category: peptide antibiotic]] | [[Category: peptide antibiotic]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:40:51 2008'' |
Revision as of 13:40, 21 February 2008
|
GRAMICIDIN D FROM BACILLUS BREVIS (ETHANOL SOLVATE)
Overview
Gramicidin D (gD) is a naturally occurring ionophoric antibiotic that forms membrane channels specific for monovalent cations. The crystal structure of the RbCl complex of gD has been determined at 1.14 A resolution from low-temperature (100 K) synchrotron-radiation data with a final R of 16%. The structure was refined with anisotropic temperature factors for all non-H atoms and with partial occupancies for many of them. The asymmetric unit in the crystal contains four crystallographically independent molecules that form two right-handed antiparallel double-stranded dimers. There are seven distinct rubidium-binding sites in each dimeric channel. The occupancy factors of Rb cations are between 0.11 and 0.35 and the total ion contents of the two crystallographically independent channels are 1.59 and 1.22 ions, respectively. Although each channel is 'chemically symmetrical', the side-chain conformations, the distributions of rubidium cations and their binding sites in the two independent channels are not. Cations are 'coordinated' by delocalized pi-electrons of three to five carbonyl groups that together with peptide backbone chains form the gramicidin channel walls. The water:cation ratio in the channel interior is four or five:one, and five or six waters separate Rb cations during their passage through the channel.
About this Structure
1W5U is a Single protein structure of sequence from Brevibacillus brevis with , , and as ligands. Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Structure of gramicidin D-RbCl complex at atomic resolution from low-temperature synchrotron data: interactions of double-stranded gramicidin channel contents and cations with channel wall., Glowka ML, Olczak A, Bojarska J, Szczesio M, Duax WL, Burkhart BM, Pangborn WA, Langs DA, Wawrzak Z, Acta Crystallogr D Biol Crystallogr. 2005 Apr;61(Pt 4):433-41. Epub 2005, Mar 24. PMID:15805598
Page seeded by OCA on Thu Feb 21 15:40:51 2008
Categories: Brevibacillus brevis | Single protein | Bojarska, J. | Burkhart, B M. | Duax, W L. | Glowka, M L. | Langs, D A. | Olczak, A. | Pangborn, W A. | Szczesio, M. | Wawrzak, Z. | CL | EOH | FOR | RB | Gramicidin double-stranded channel | Gramicidin rbcl complex | High resolution data | Peptide antibiotic
