Crystallization of the functional domain of human thrombopoietin using an antigen-binding fragment derived from neutralizing monoclonal antibody

Autor: Michael D. Feese, Ryota Kuroki, Taro Tamada, Yoichi Kato, Masako Hirose, Hiroshi Watarai, Hideki Shigematsu, Yoshitake Maeda, Tomoyuki Tahara, Hiroshi Miyazaki, Takashi Kato
Rok vydání: 2002
Předmět:
Zdroj: Acta Crystallographica Section D Biological Crystallography. 58:856-858
ISSN: 1399-0047
0907-4449
DOI: 10.1107/s0907444902004791
Popis: Thrombopoietin (TPO) is a cytokine which primarily stimulates megakaryocytopoiesis and thrombopoiesis. The functional domain of TPO (TPO(163)) consisting of the N-terminal 163 amino acids was prepared and crystallized. Since the crystallization of TPO(163) was unsuccessful using the standard screening methods, a Fab fragment derived from a neutralizing monoclonal antibody was used for crystallization. It was found that the TPO(163)-Fab complex crystallized reproducibly in 0.1 M potassium phosphate buffer pH 6.0 containing 20-25% polyethylene glycol 4000. Thin crystals (0.2 x 0.2 x 0.02 mm) grew in two space groups: P2(1), with unit-cell parameters a = 133.20, b = 46.71, c = 191.47 A, beta = 90.24 degrees, and C2, with unit-cell parameters a = 131.71, b = 46.48, c = 184.63 A, beta = 90.42 degrees. The results of a molecular-replacement analysis indicate that the Fab molecules interact with each other and provide a suitable interface for crystallization.
Databáze: OpenAIRE