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| == Function == | | == Function == |
| [https://www.uniprot.org/uniprot/Q2K0Z2_RHIEC Q2K0Z2_RHIEC] | | [https://www.uniprot.org/uniprot/Q2K0Z2_RHIEC Q2K0Z2_RHIEC] |
| <div style="background-color:#fffaf0;">
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| == Publication Abstract from PubMed ==
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| Rhizobium etli, a nitrogen-fixing bacterial symbiont of legume plants, encodes an essential L-asparaginase (ReAV) with no sequence homology to known enzymes with this activity. High-resolution crystal structures of ReAV show indeed a structurally distinct, dimeric enzyme, with some resemblance to glutaminases and beta-lactamases. However, ReAV has no glutaminase or lactamase activity, and at pH 9 its allosteric asparaginase activity is relatively high, with Km for L-Asn at 4.2 mM and kcat of 438 s(-1). The active site of ReAV, deduced from structural comparisons and confirmed by mutagenesis experiments, contains a highly specific Zn(2+) binding site without a catalytic role. The extensive active site includes residues with unusual chemical properties. There are two Ser-Lys tandems, all connected through a network of H-bonds to the Zn center, and three tightly bound water molecules near Ser48, which clearly indicate the catalytic nucleophile.
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| , PMID:34795296<ref>PMID:34795296</ref>
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| From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
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| </div>
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| <div class="pdbe-citations 7os3" style="background-color:#fffaf0;"></div>
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| ==See Also== | | ==See Also== |
| *[[Asparaginase 3D structures|Asparaginase 3D structures]] | | *[[Asparaginase 3D structures|Asparaginase 3D structures]] |
| == References ==
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| <references/>
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| __TOC__ | | __TOC__ |
| </StructureSection> | | </StructureSection> |
