1onj
From Proteopedia
(New page: 200px<br /><applet load="1onj" size="450" color="white" frame="true" align="right" spinBox="true" caption="1onj, resolution 1.555Å" /> '''Crystal structure o...) |
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| - | [[Image:1onj.gif|left|200px]]<br /><applet load="1onj" size=" | + | [[Image:1onj.gif|left|200px]]<br /><applet load="1onj" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1onj, resolution 1.555Å" /> | caption="1onj, resolution 1.555Å" /> | ||
'''Crystal structure of Atratoxin-b from Chinese cobra venom of Naja atra'''<br /> | '''Crystal structure of Atratoxin-b from Chinese cobra venom of Naja atra'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Atratoxin-b, a short-chain alpha-neurotoxin purified from Naja atra | + | Atratoxin-b, a short-chain alpha-neurotoxin purified from Naja atra (mainland Chinese cobra) venom using a three-step chromatography procedure, has an apparent molecular mass of 6950 Da with an alkaline pI value (>9.5) and consists of one single polypeptide chain as estimated by MALDI-TOF mass spectrometry and SDS-PAGE. The protein is toxic to mice, with an in vitro LD(50) of about 0.18 mg kg(-1). Its N-terminal amino-acid sequence, LECHNQQSSQTPTIT, displays a very high homology to those of other alpha-neurotoxins. The overall three-dimensional structure of atratoxin-b is very similar to that of the homologous erabutoxin-a, as shown by the crystallographic molecular replacement and preliminary refinement results, with an R factor and R(free) of 27 and 29%, respectively. The microcrystal slowly grew to dimensions of approximate 0.1 x 0.1 x 0.15 mm over eight months using hanging-drop vapour-diffusion method. It gave a set of diffraction data to 1.56 A resolution using X-rays of wavelength 1.1516 A generated by the X-ray Diffraction and Scattering Station of beamline U7B at the National Synchrotron Radiation Laboratory (Hefei, China); this is the first example of the use of this beamline in protein crystallography. The crystals belong to the tetragonal space group P4(1)2(1)2, with unit-cell parameters a = 49.28, c = 44.80 A, corresponding to one molecule per asymmetric unit and a volume-to-mass ratio of 1.96 A(3) Da(-1). |
==About this Structure== | ==About this Structure== | ||
| - | 1ONJ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Naja_atra Naja atra] with SO4 as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1ONJ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Naja_atra Naja atra] with <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1ONJ OCA]. |
==Reference== | ==Reference== | ||
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[[Category: three-finger protein]] | [[Category: three-finger protein]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:19:38 2008'' |
Revision as of 12:19, 21 February 2008
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Crystal structure of Atratoxin-b from Chinese cobra venom of Naja atra
Overview
Atratoxin-b, a short-chain alpha-neurotoxin purified from Naja atra (mainland Chinese cobra) venom using a three-step chromatography procedure, has an apparent molecular mass of 6950 Da with an alkaline pI value (>9.5) and consists of one single polypeptide chain as estimated by MALDI-TOF mass spectrometry and SDS-PAGE. The protein is toxic to mice, with an in vitro LD(50) of about 0.18 mg kg(-1). Its N-terminal amino-acid sequence, LECHNQQSSQTPTIT, displays a very high homology to those of other alpha-neurotoxins. The overall three-dimensional structure of atratoxin-b is very similar to that of the homologous erabutoxin-a, as shown by the crystallographic molecular replacement and preliminary refinement results, with an R factor and R(free) of 27 and 29%, respectively. The microcrystal slowly grew to dimensions of approximate 0.1 x 0.1 x 0.15 mm over eight months using hanging-drop vapour-diffusion method. It gave a set of diffraction data to 1.56 A resolution using X-rays of wavelength 1.1516 A generated by the X-ray Diffraction and Scattering Station of beamline U7B at the National Synchrotron Radiation Laboratory (Hefei, China); this is the first example of the use of this beamline in protein crystallography. The crystals belong to the tetragonal space group P4(1)2(1)2, with unit-cell parameters a = 49.28, c = 44.80 A, corresponding to one molecule per asymmetric unit and a volume-to-mass ratio of 1.96 A(3) Da(-1).
About this Structure
1ONJ is a Single protein structure of sequence from Naja atra with as ligand. Full crystallographic information is available from OCA.
Reference
Purification, N-terminal sequencing, crystallization and preliminary structural determination of atratoxin-b, a short-chain alpha-neurotoxin from Naja atra venom., Lou X, Tu X, Pan G, Xu C, Fan R, Lu W, Deng W, Rao P, Teng M, Niu L, Acta Crystallogr D Biol Crystallogr. 2003 Jun;59(Pt 6):1038-42. Epub 2003, May 23. PMID:12777767
Page seeded by OCA on Thu Feb 21 14:19:38 2008
Categories: Naja atra | Single protein | Deng, W. | Fan, R. | Lou, X. | Lu, W. | Niu, L. | Pan, G. | Rao, P. | Teng, M. | Tu, X. | Xu, C. | SO4 | Beta-turn-beta | Three-finger protein
