Structural highlights
Function
[PDX13_ARATH] Catalyzes the formation of pyridoxal 5'-phosphate from ribose 5-phosphate (RBP), glyceraldehyde 3-phosphate (G3P) and ammonia. The ammonia is provided by PDX2. Can also use ribulose 5-phosphate and dihydroxyacetone phosphate as substrates, resulting from enzyme-catalyzed isomerization of RBP and G3P, respectively. Also plays an indirect role in resistance to singlet oxygen-generating photosensitizers.[1] [2] [3]
Publication Abstract from PubMed
The Pdx1 enzyme catalyses condensation of two carbohydrates and ammonia to form pyridoxal 5-phosphate (PLP) via an imine relay mechanism of carbonyl intermediates. The I333 intermediate characterised here using structural, UV-vis absorption spectroscopy and mass spectrometry analyses rationalises stereoselective deprotonation and subsequent substrate assisted phosphate elimination, central to PLP biosynthesis.
Trapping and structural characterisation of a covalent intermediate in vitamin B6 biosynthesis catalysed by the Pdx1 PLP synthase.,Rodrigues MJ, Giri N, Royant A, Zhang Y, Bolton R, Evans G, Ealick SE, Begley T, Tews I RSC Chem Biol. 2021 Oct 25;3(2):227-230. doi: 10.1039/d1cb00160d. eCollection, 2022 Feb 9. PMID:35360887[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Tambasco-Studart M, Titiz O, Raschle T, Forster G, Amrhein N, Fitzpatrick TB. Vitamin B6 biosynthesis in higher plants. Proc Natl Acad Sci U S A. 2005 Sep 20;102(38):13687-92. Epub 2005 Sep 12. PMID:16157873 doi:http://dx.doi.org/0506228102
- ↑ Chen H, Xiong L. Pyridoxine is required for post-embryonic root development and tolerance to osmotic and oxidative stresses. Plant J. 2005 Nov;44(3):396-408. PMID:16236150 doi:http://dx.doi.org/TPJ2538
- ↑ Tambasco-Studart M, Tews I, Amrhein N, Fitzpatrick TB. Functional analysis of PDX2 from Arabidopsis, a glutaminase involved in vitamin B6 biosynthesis. Plant Physiol. 2007 Jun;144(2):915-25. Epub 2007 Apr 27. PMID:17468224 doi:http://dx.doi.org/10.1104/pp.107.096784
- ↑ Rodrigues MJ, Giri N, Royant A, Zhang Y, Bolton R, Evans G, Ealick SE, Begley T, Tews I. Trapping and structural characterisation of a covalent intermediate in vitamin B6 biosynthesis catalysed by the Pdx1 PLP synthase. RSC Chem Biol. 2021 Oct 25;3(2):227-230. doi: 10.1039/d1cb00160d. eCollection, 2022 Feb 9. PMID:35360887 doi:http://dx.doi.org/10.1039/d1cb00160d
