Structural highlights
4e3x is a 2 chain structure with sequence from Lk3 transgenic mice. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
|
| Ligands: | , , |
| Related: | 4e3u, 4e3v, 4e3w |
| Gene: | Aldh4a1 (LK3 transgenic mice) |
| Activity: | 1-pyrroline-5-carboxylate dehydrogenase, with EC number 1.5.1.12 |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[AL4A1_MOUSE] Irreversible conversion of delta-1-pyrroline-5-carboxylate (P5C), derived either from proline or ornithine, to glutamate. This is a necessary step in the pathway interconnecting the urea and tricarboxylic acid cycles. The preferred substrate is glutamic gamma-semialdehyde, other substrates include succinic, glutaric and adipic semialdehydes (By similarity).
Publication Abstract from PubMed
L-Proline is one of Mother Nature's cryoprotectants. Plants and yeast accumulate proline under freeze-induced stress and the use of proline in the cryopreservation of biological samples is well established. Here, it is shown that L-proline is also a useful cryoprotectant for protein crystallography. Proline was used to prepare crystals of lysozyme, xylose isomerase, histidine acid phosphatase and 1-pyrroline-5-carboxylate dehydrogenase for low-temperature data collection. The crystallization solutions in these test cases included the commonly used precipitants ammonium sulfate, sodium chloride and polyethylene glycol and spanned the pH range 4.6-8.5. Thus, proline is compatible with typical protein-crystallization formulations. The proline concentration needed for cryoprotection of these crystals is in the range 2.0-3.0 M. Complete data sets were collected from the proline-protected crystals. Proline performed as well as traditional cryoprotectants based on the diffraction resolution and data-quality statistics. The structures were refined to assess the binding of proline to these proteins. As observed with traditional cryoprotectants such as glycerol and ethylene glycol, the electron-density maps clearly showed the presence of proline molecules bound to the protein. In two cases, histidine acid phosphatase and 1-pyrroline-5-carboxylate dehydrogenase, proline binds in the active site. It is concluded that L-proline is an effective cryoprotectant for protein crystallography.
Proline: Mother Nature's cryoprotectant applied to protein crystallography.,Pemberton TA, Still BR, Christensen EM, Singh H, Srivastava D, Tanner JJ Acta Crystallogr D Biol Crystallogr. 2012 Aug;68(Pt 8):1010-8. Epub 2012 Jul 17. PMID:22868767[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Pemberton TA, Still BR, Christensen EM, Singh H, Srivastava D, Tanner JJ. Proline: Mother Nature's cryoprotectant applied to protein crystallography. Acta Crystallogr D Biol Crystallogr. 2012 Aug;68(Pt 8):1010-8. Epub 2012 Jul 17. PMID:22868767 doi:10.1107/S0907444912019580
