title: The taming of small heat-shock proteins: crystallization of the alpha-crystallin domain from human Hsp27.
abstract: Small heat-shock proteins (sHsps) are ubiquitous molecular chaperones. sHsps function as homooligomers or heterooligomers that are prone to subunit exchange and structural plasticity. Here, a procedure for obtaining diffraction-quality crystals of the alpha-crystallin domain of human Hsp27 is presented. Initially, limited proteolysis was used to delineate the corresponding stable fragment (residues 90-171). This fragment could be crystallized, but examination of the crystals using X-rays indicated partial disorder. The surface-entropy reduction approach was applied to ameliorate the crystal quality. Consequently, a double mutant E125A/E126A of the 90-171 fragment yielded well ordered crystals that diffracted to 2.0 A resolution.
authors.affiliation: Laboratory for Biocrystallography, Department of Pharmaceutical Sciences, Katholieke Universiteit Leuven, Belgium. ebaranov@vub.ac.be
authors.forename: E V
authors.initials: EV
authors.lastname: Baranova
authors.forename: S
authors.initials: S
authors.lastname: Beelen
authors.forename: N B
authors.initials: NB
authors.lastname: Gusev
authors.forename: S V
authors.initials: SV
authors.lastname: Strelkov
mesh_terms: D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D018360:Crystallography, X-Ray; D055551:HSP27 Heat-Shock Proteins / Q000737:chemistry* / Q000235:genetics; D006360:Heat-Shock Proteins; D006801:Humans; D018832:Molecular Chaperones; D008969:Molecular Sequence Data; D016296:Mutagenesis; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D038201:alpha-Crystallins / Q000737:chemistry* / Q000235:genetics
chemical_list: D055551:HSP27 Heat-Shock Proteins; C057725:HSPB1 protein, human; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D010446:Peptide Fragments; D011994:Recombinant Proteins; D038201:alpha-Crystallins