5f9s
From Proteopedia
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== Disease == | == Disease == | ||
[[http://www.uniprot.org/uniprot/SPYA_HUMAN SPYA_HUMAN]] Defects in AGXT are the cause of hyperoxaluria primary type 1 (HP1) [MIM:[http://omim.org/entry/259900 259900]]; also known as primary hyperoxaluria type I (PH1) and oxalosis I. HP1 is a rare autosomal recessive inborn error of glyoxylate metabolism characterized by increased excretion of oxalate and glycolate, and the progressive accumulation of insoluble calcium oxalate in the kidney and urinary tract.<ref>PMID:1703535</ref> <ref>PMID:2039493</ref> <ref>PMID:1349575</ref> <ref>PMID:1301173</ref> <ref>PMID:8101040</ref> <ref>PMID:9192270</ref> <ref>PMID:9604803</ref> <ref>PMID:10394939</ref> <ref>PMID:10453743</ref> <ref>PMID:10541294</ref> <ref>PMID:10862087</ref> <ref>PMID:10960483</ref> <ref>PMID:12559847</ref> <ref>PMID:12777626</ref> <ref>PMID:15253729</ref> <ref>PMID:15849466</ref> <ref>PMID:15961946</ref> <ref>PMID:15963748</ref> | [[http://www.uniprot.org/uniprot/SPYA_HUMAN SPYA_HUMAN]] Defects in AGXT are the cause of hyperoxaluria primary type 1 (HP1) [MIM:[http://omim.org/entry/259900 259900]]; also known as primary hyperoxaluria type I (PH1) and oxalosis I. HP1 is a rare autosomal recessive inborn error of glyoxylate metabolism characterized by increased excretion of oxalate and glycolate, and the progressive accumulation of insoluble calcium oxalate in the kidney and urinary tract.<ref>PMID:1703535</ref> <ref>PMID:2039493</ref> <ref>PMID:1349575</ref> <ref>PMID:1301173</ref> <ref>PMID:8101040</ref> <ref>PMID:9192270</ref> <ref>PMID:9604803</ref> <ref>PMID:10394939</ref> <ref>PMID:10453743</ref> <ref>PMID:10541294</ref> <ref>PMID:10862087</ref> <ref>PMID:10960483</ref> <ref>PMID:12559847</ref> <ref>PMID:12777626</ref> <ref>PMID:15253729</ref> <ref>PMID:15849466</ref> <ref>PMID:15961946</ref> <ref>PMID:15963748</ref> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | The alanine:glyoxylate aminotransferase (AGT), a hepatocyte-specific pyridoxal-5'-phosphate (PLP) dependent enzyme, transaminates L-alanine and glyoxylate to glycine and pyruvate, thus detoxifying glyoxylate and preventing pathological oxalate precipitation in tissues. In the widely accepted catalytic mechanism of the aminotransferase family, the lysine binding to PLP acts as a catalyst in the stepwise 1,3-proton transfer, interconverting the external aldimine to ketimine. This step requires protonation by a conserved aspartate of the pyridine nitrogen of PLP to enhance its ability to stabilize the carbanionic intermediate. The aspartate residue is also responsible for a significant geometrical distortion of the internal aldimine, crucial for catalysis. We present the structure of human AGT in which complete X-ray photoreduction of the Schiff base has occurred. This result, together with two crystal structures of the conserved aspartate pathogenic variant (D183N) and the molecular modeling of the transaldimination step, led us to propose that an interplay of opposite forces, which we named spring mechanism, finely tunes PLP geometry during catalysis and is essential to move the external aldimine in the correct position in order for the 1,3-proton transfer to occur. | ||
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| + | Radiation damage at the active site of human alanine:glyoxylate aminotransferase reveals that the cofactor position is finely tuned during catalysis.,Giardina G, Paiardini A, Montioli R, Cellini B, Voltattorni CB, Cutruzzola F Sci Rep. 2017 Sep 15;7(1):11704. doi: 10.1038/s41598-017-11948-w. PMID:28916765<ref>PMID:28916765</ref> | ||
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| + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| + | </div> | ||
| + | <div class="pdbe-citations 5f9s" style="background-color:#fffaf0;"></div> | ||
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| + | ==See Also== | ||
| + | *[[Aminotransferase|Aminotransferase]] | ||
== References == | == References == | ||
<references/> | <references/> | ||
Revision as of 09:38, 27 September 2017
Crystal structure of human Alanine:Glyoxylate Aminotransferase major allele (AGT-Ma) at 1.7 Angstrom; internal aldimine with PLP in the active site
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