Open AccessCrystallization and preliminary crystallographic analysis of the complex between triiodothyronine and the bb ′ fragment of rat protein disulfide isomerase
Author(s) -
Hashimoto Shoko,
Ito Len,
Okumura Masaki,
Shibano Tomohisa,
Nawata Marina,
Kumasaka Takashi,
Yamaguchi Hiroshi,
Imaoka Susumu
Publication year - 2012
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309112007439
Subject(s) - protein disulfide isomerase , crystallization , chemistry , crystallography , disulfide bond , crystal structure , stereochemistry , biochemistry , organic chemistry
Protein disulfide isomerase (PDI) is a multifunctional protein that catalyzes the formation of a disulfide bond in nascent and misfolded proteins and is also known to bind to the thyroid hormone triiodothyronine (T3). When T3 is bound to PDI its catalytic activity is inhibited, but the biological function of this binding is not well understood. In previous studies, it was found that T3 binds to the bb ′ fragment of PDI. Therefore, to clarify the structure of the complex consisting of PDI bound to T3, a crystallographic analysis of the three‐dimensional structure of the T3–rat PDI bb ′ complex was performed. Native bb ′ crystals and T3– bb ′ complex crystals were both obtained using the hanging‐drop vapour‐diffusion technique with 1.6 M trisodium citrate pH 6.2 as a precipitant. The space group of the native bb ′ crystals was found to be C 222, with unit‐cell parameters a = 94.8, b = 114.9, c = 182.9 Å, while the space group of the T3– bb ′ complex crystals was P 2 1 2 1 2 1 , with unit‐cell parameters a = 99.9, b = 184.5, c = 232.2 Å. Diffraction data for the native and complex crystals were collected to resolutions of 3.06 and 3.00 Å, respectively.