Structural highlights
5svc is a 6 chain structure with sequence from Xanp2. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
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| Ligands: | , , |
| Related: | 5svb |
| Gene: | acxB, Xaut_3510 (XANP2), acxA, Xaut_3509 (XANP2), acxC, Xaut_3511 (XANP2) |
| Activity: | Acetone carboxylase, with EC number 6.4.1.6 |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[ACXB_XANP2] Catalyzes the carboxylation of acetone to form acetoacetate. Has a reduced activity on butanone, and no activity on 2-pentatone, 3-pentatone, 2-hexanone, chloroacetone, pyruvate, phosphoenolpyruvate, acetaldehyde, propionaldehyde and propylene oxide.[1] [ACXC_XANP2] Catalyzes the carboxylation of acetone to form acetoacetate. Has a reduced activity on butanone, and no activity on 2-pentatone, 3-pentatone, 2-hexanone, chloroacetone, pyruvate, phosphoenolpyruvate, acetaldehyde, propionaldehyde and propylene oxide.[2] [ACXA_XANP2] Catalyzes the carboxylation of acetone to form acetoacetate. Has a reduced activity on butanone, and no activity on 2-pentatone, 3-pentatone, 2-hexanone, chloroacetone, pyruvate, phosphoenolpyruvate, acetaldehyde, propionaldehyde and propylene oxide.[3]
Publication Abstract from PubMed
Microorganisms use carboxylase enzymes to form new carbon-carbon bonds by introducing carbon dioxide gas (CO2) or its hydrated form, bicarbonate (HCO3-), into target molecules. Acetone carboxylases (ACs) catalyze the conversion of substrates acetone and HCO3- to form the product acetoacetate. Many bicarbonate-incorporating carboxylases rely on the organic cofactor biotin for the activation of bicarbonate. ACs contain metal ions but not organic cofactors, and use ATP to activate substrates through phosphorylation. How the enzyme coordinates these phosphorylation events and new C-C bond formation in the absence of biotin has remained a mystery since these enzymes were discovered. The first structural rationale for acetone carboxylation is presented here, focusing on the 360 kDa (alphabetagamma)2 heterohexameric AC from Xanthobacter autotrophicus in the ligand-free, AMP-bound, and acetate coordinated states. These structures suggest successive steps in a catalytic cycle revealing that AC undergoes large conformational changes coupled to substrate activation by ATP to perform C-C bond ligation at a distant Mn center. These results illustrate a new chemical strategy for the conversion of CO2 into biomass, a process of great significance to the global carbon cycle.
Structural Basis for the Mechanism of ATP-Dependent Acetone Carboxylation.,Mus F, Eilers BJ, Alleman AB, Kabasakal BV, Wells JN, Murray JW, Nocek BP, DuBois JL, Peters JW Sci Rep. 2017 Aug 3;7(1):7234. doi: 10.1038/s41598-017-06973-8. PMID:28775283[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Sluis MK, Ensign SA. Purification and characterization of acetone carboxylase from Xanthobacter strain Py2. Proc Natl Acad Sci U S A. 1997 Aug 5;94(16):8456-61. PMID:9237998
- ↑ Sluis MK, Ensign SA. Purification and characterization of acetone carboxylase from Xanthobacter strain Py2. Proc Natl Acad Sci U S A. 1997 Aug 5;94(16):8456-61. PMID:9237998
- ↑ Sluis MK, Ensign SA. Purification and characterization of acetone carboxylase from Xanthobacter strain Py2. Proc Natl Acad Sci U S A. 1997 Aug 5;94(16):8456-61. PMID:9237998
- ↑ Mus F, Eilers BJ, Alleman AB, Kabasakal BV, Wells JN, Murray JW, Nocek BP, DuBois JL, Peters JW. Structural Basis for the Mechanism of ATP-Dependent Acetone Carboxylation. Sci Rep. 2017 Aug 3;7(1):7234. doi: 10.1038/s41598-017-06973-8. PMID:28775283 doi:http://dx.doi.org/10.1038/s41598-017-06973-8
