2A6U

pH evolution of tetragonal HEWL at 4 degrees Celcius.

2A6U の概要

• エントリーDOI: 10.2210/pdb2a6u/pdb
• 分子名称: Lysozyme C (1 entity in total)
• 機能のキーワード: powder diffraction, rietveld refinement, lysozyme, hydrolase
• 由来する生物種: Gallus gallus (chicken)
• 細胞内の位置: Secreted: P00698
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 14331.16

構造登録者

Margiolaki, I. (登録日: 2005-07-04, 公開日: 2006-01-03, 最終更新日: 2024-11-20)

主引用文献

Basso, S.,Fitch, A.N.,Fox, G.C.,Margiolaki, I.,Wright, J.P.
High-throughput phase-diagram mapping via powder diffraction: a case study of HEWL versus pH.
Acta Crystallogr.,Sect.D, 61:1612-1625, 2005

PubMed Abstract: 44 samples of tetragonal hen egg-white lysozyme (HEWL) were obtained as a series of polycrystalline precipitates at 277 K and room temperature in the pH range between 6.56 and 3.33. The precipitates were investigated by the collection of high-resolution powder X-ray diffraction data at 295 K, which reveal the tetragonal or orthorhombic forms of lysozyme depending on the temperature and pH of crystallization. The use of a new robotic sample changer greatly facilitated these measurements. LeBail analyses of the powder patterns display a characteristic behaviour for the pH dependence of the tetragonal unit-cell parameters of HEWL crystallized at both temperatures. More detailed analysis shows that molecular replacement can give a suitable starting point for structural refinements, illustrating that powder data can be sufficient for this approach. Pawley or Rietveld refinements that fit a single model to four data sets simultaneously from four samples crystallized at pH values across the range studied benefit from improved powder data quality via the anisotropic changes in the unit cell. The Rietveld analysis gave an average structural model with excellent goodness of fit and stereochemistry.

PubMed: 16301795
DOI: 10.1107/S0907444905031963

実験手法

POWDER DIFFRACTION