Production, crystallization and preliminary crystallographic study of the major cat allergen Fel d 1

The domestic cat (Felis domesticus) is an important cause of allergic disease worldwide. The major cat allergen 1 (Fel d 1) has been expressed in Escherichia coli, purified and refolded in a soluble form. Crystals of Fel d 1 were obtained in 13% 2-methyl-2,4-pentanediol, 0.1 M sodium acetate pH 4.8. The Fel d 1 crystals belong to space group P2(1), with unit-cell parameters a = 43.3, b = 51.5, c = 67.7 A, and diffract to 1.9 A resolution.