Premium
Ca 2+ ‐Binding domain VI of rat calpain is a homodimer in solution: Hydrodynamic, crystallization and preliminary X‐ray diffraction studies
Author(s) -
Blanchard Helen,
Li Yunge,
Cygler Miroslaw,
Kay Cyril M.,
Arthur J. Simon C.,
Davies Peter L.,
Elce John S.
Publication year - 1996
Publication title -
protein science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.353
H-Index - 175
eISSN - 1469-896X
pISSN - 0961-8368
DOI - 10.1002/pro.5560050317
Subject(s) - crystallization , x ray crystallography , crystallography , diffraction , chemistry , domain (mathematical analysis) , biophysics , x ray , physics , biology , optics , organic chemistry , mathematical analysis , mathematics
Abstract Abstract: The 21‐kDa calcium‐binding domain (VI) of the small subunit of rat calpain II has been expressed in Escherichia coli , purified, and crystallized. Two orthorhombic crystal forms have been obtained: space group P2 1 2 1 2 1 with a = 50.3, b = 56.5, c = 141.3 Å; and space group C222 1 with a = 69.4, b = 73.9, c = 157.4 Å. Diffraction data have been collected to 2.4 Å. Sedimentation equilibrium, dynamic light scattering, and gel‐permeation chromatography indicate that domain VI exists as a homodimer in solution. In accordance with the protein's behavior in solution, each crystal form contains two molecules per asymmetric unit. Screening for heavy‐atom derivatives is in progress. To decrease the sensitivity to mercurials and to aid in the search for useful derivatives, Cys‐to‐Ser mutants have been prepared, expressed, and crystallized.