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1lw4
From Proteopedia
(New page: 200px<br /><applet load="1lw4" size="450" color="white" frame="true" align="right" spinBox="true" caption="1lw4, resolution 1.9Å" /> '''X-ray structure of L-...) |
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| - | [[Image:1lw4.gif|left|200px]]<br /><applet load="1lw4" size=" | + | [[Image:1lw4.gif|left|200px]]<br /><applet load="1lw4" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1lw4, resolution 1.9Å" /> | caption="1lw4, resolution 1.9Å" /> | ||
'''X-ray structure of L-Threonine Aldolase (low-specificity) in complex with L-allo-threonine'''<br /> | '''X-ray structure of L-Threonine Aldolase (low-specificity) in complex with L-allo-threonine'''<br /> | ||
==Overview== | ==Overview== | ||
| - | L-Threonine acetaldehyde-lyase (threonine aldolase, TA) is a | + | L-Threonine acetaldehyde-lyase (threonine aldolase, TA) is a pyridoxal-5'-phosphate-dependent (PLP) enzyme that catalyzes conversion of L-threonine or L-allo-threonine to glycine and acetaldehyde in a secondary glycine biosynthetic pathway. X-ray structures of Thermatoga maritima TA have been determined as the apo-enzyme at 1.8 A resolution and bound to substrate L-allo-threonine and product glycine at 1.9 and 2.0 A resolution, respectively. Despite low pairwise sequence identities, TA is a member of aspartate aminotransferase (AATase) fold family of PLP enzymes. The enzyme forms a 222 homotetramer with the PLP cofactor bound via a Schiff-base linkage to Lys199 within a domain interface. The structure reveals bound calcium and chloride ions that appear to contribute to catalysis and oligomerization, respectively. Although L-threonine and L-allo-threonine are substrates for T. maritima TA, enzymatic assays revealed a strong preference for L-allo-threonine. Structures of the external aldimines with substrate/product reveal a pair of histidines that may provide flexibility in substrate recognition. Variation in the threonine binding pocket may explain preferences for L-allo-threonine versus L-threonine among TA family members. |
==About this Structure== | ==About this Structure== | ||
| - | 1LW4 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermotoga_maritima Thermotoga maritima] with CA, CL, TLP and PLP as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Threonine_aldolase Threonine aldolase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.2.5 4.1.2.5] Full crystallographic information is available from [http:// | + | 1LW4 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermotoga_maritima Thermotoga maritima] with <scene name='pdbligand=CA:'>CA</scene>, <scene name='pdbligand=CL:'>CL</scene>, <scene name='pdbligand=TLP:'>TLP</scene> and <scene name='pdbligand=PLP:'>PLP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Threonine_aldolase Threonine aldolase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.2.5 4.1.2.5] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LW4 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Thermotoga maritima]] | [[Category: Thermotoga maritima]] | ||
[[Category: Threonine aldolase]] | [[Category: Threonine aldolase]] | ||
| - | [[Category: Burley, S | + | [[Category: Burley, S K.]] |
| - | [[Category: Kielkopf, C | + | [[Category: Kielkopf, C L.]] |
| - | [[Category: NYSGXRC, New | + | [[Category: NYSGXRC, New York Structural GenomiX Research Consortium.]] |
[[Category: CA]] | [[Category: CA]] | ||
[[Category: CL]] | [[Category: CL]] | ||
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[[Category: threonine]] | [[Category: threonine]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:49:06 2008'' |
Revision as of 11:49, 21 February 2008
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X-ray structure of L-Threonine Aldolase (low-specificity) in complex with L-allo-threonine
Overview
L-Threonine acetaldehyde-lyase (threonine aldolase, TA) is a pyridoxal-5'-phosphate-dependent (PLP) enzyme that catalyzes conversion of L-threonine or L-allo-threonine to glycine and acetaldehyde in a secondary glycine biosynthetic pathway. X-ray structures of Thermatoga maritima TA have been determined as the apo-enzyme at 1.8 A resolution and bound to substrate L-allo-threonine and product glycine at 1.9 and 2.0 A resolution, respectively. Despite low pairwise sequence identities, TA is a member of aspartate aminotransferase (AATase) fold family of PLP enzymes. The enzyme forms a 222 homotetramer with the PLP cofactor bound via a Schiff-base linkage to Lys199 within a domain interface. The structure reveals bound calcium and chloride ions that appear to contribute to catalysis and oligomerization, respectively. Although L-threonine and L-allo-threonine are substrates for T. maritima TA, enzymatic assays revealed a strong preference for L-allo-threonine. Structures of the external aldimines with substrate/product reveal a pair of histidines that may provide flexibility in substrate recognition. Variation in the threonine binding pocket may explain preferences for L-allo-threonine versus L-threonine among TA family members.
About this Structure
1LW4 is a Single protein structure of sequence from Thermotoga maritima with , , and as ligands. Active as Threonine aldolase, with EC number 4.1.2.5 Full crystallographic information is available from OCA.
Reference
X-ray structures of threonine aldolase complexes: structural basis of substrate recognition., Kielkopf CL, Burley SK, Biochemistry. 2002 Oct 1;41(39):11711-20. PMID:12269813
Page seeded by OCA on Thu Feb 21 13:49:06 2008
Categories: Single protein | Thermotoga maritima | Threonine aldolase | Burley, S K. | Kielkopf, C L. | NYSGXRC, New York Structural GenomiX Research Consortium. | CA | CL | PLP | TLP | Enzyme | New york structural genomix research consortium | Nysgxrc | Plp | Product complex | Protein structure initiative | Psi | Pyridoxal-5-phosphate | Structural genomics | Threonine
