1qgn: Difference between revisions
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[[Image:1qgn.jpg|left|200px]] | [[Image:1qgn.jpg|left|200px]] | ||
'''CYSTATHIONINE GAMMA-SYNTHASE FROM NICOTIANA TABACUM''' | {{Structure | ||
|PDB= 1qgn |SIZE=350|CAPTION= <scene name='initialview01'>1qgn</scene>, resolution 2.9Å | |||
|SITE= | |||
|LIGAND= <scene name='pdbligand=PLP:PYRIDOXAL-5'-PHOSPHATE'>PLP</scene> | |||
|ACTIVITY= [http://en.wikipedia.org/wiki/Cystathionine_gamma-synthase Cystathionine gamma-synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.5.1.48 2.5.1.48] | |||
|GENE= METB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=4097 Nicotiana tabacum]) | |||
}} | |||
'''CYSTATHIONINE GAMMA-SYNTHASE FROM NICOTIANA TABACUM''' | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
1QGN is a [ | 1QGN is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Nicotiana_tabacum Nicotiana tabacum]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QGN OCA]. | ||
==Reference== | ==Reference== | ||
The crystal structure of cystathionine gamma-synthase from Nicotiana tabacum reveals its substrate and reaction specificity., Steegborn C, Messerschmidt A, Laber B, Streber W, Huber R, Clausen T, J Mol Biol. 1999 Jul 30;290(5):983-96. PMID:[http:// | The crystal structure of cystathionine gamma-synthase from Nicotiana tabacum reveals its substrate and reaction specificity., Steegborn C, Messerschmidt A, Laber B, Streber W, Huber R, Clausen T, J Mol Biol. 1999 Jul 30;290(5):983-96. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10438597 10438597] | ||
[[Category: Cystathionine gamma-synthase]] | [[Category: Cystathionine gamma-synthase]] | ||
[[Category: Nicotiana tabacum]] | [[Category: Nicotiana tabacum]] | ||
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[[Category: pyridoxal 5'-phosphate]] | [[Category: pyridoxal 5'-phosphate]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 13:37:16 2008'' | ||
Revision as of 11:37, 20 March 2008
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| 1qgn, resolution 2.9Å | |||||||||||||
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| Ligands: | PLP | ||||||||||||
| Gene: | METB (Nicotiana tabacum) | ||||||||||||
| Activity: | Cystathionine gamma-synthase, with EC number 2.5.1.48 | ||||||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||||||
CYSTATHIONINE GAMMA-SYNTHASE FROM NICOTIANA TABACUM
Overview
Cystathionine gamma-synthase catalyses the committed step of de novo methionine biosynthesis in micro-organisms and plants, making the enzyme an attractive target for the design of new antibiotics and herbicides. The crystal structure of cystathionine gamma-synthase from Nicotiana tabacum has been solved by Patterson search techniques using the structure of Escherichia coli cystathionine gamma-synthase. The model was refined at 2.9 A resolution to a crystallographic R -factor of 20.1 % (Rfree25.0 %). The physiological substrates of the enzyme, L-homoserine phosphate and L-cysteine, were modelled into the unliganded structure. These complexes support the proposed ping-pong mechanism for catalysis and illustrate the dissimilar substrate specificities of bacterial and plant cystathionine gamma-synthases on a molecular level. The main difference arises from the binding modes of the distal substrate groups (O -acetyl/succinyl versusO -phosphate). Central in fixing the distal phosphate of the plant CGS substrate is an exposed lysine residue that is strictly conserved in plant cystathionine gamma-synthases whereas bacterial enzymes carry a glycine residue at this position. General insight regarding the reaction specificity of transsulphuration enzymes is gained by the comparison to cystathionine beta-lyase from E. coli, indicating the mechanistic importance of a second substrate binding site for L-cysteine which leads to different chemical reaction types.
About this Structure
1QGN is a Single protein structure of sequence from Nicotiana tabacum. Full crystallographic information is available from OCA.
Reference
The crystal structure of cystathionine gamma-synthase from Nicotiana tabacum reveals its substrate and reaction specificity., Steegborn C, Messerschmidt A, Laber B, Streber W, Huber R, Clausen T, J Mol Biol. 1999 Jul 30;290(5):983-96. PMID:10438597
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