title: The periplasmic E. coli chaperone Skp is a trimer in solution: biophysical and preliminary crystallographic characterization.
abstract: The 'seventeen kilodalton protein' Skp confers transient solubility on outer membrane proteins during biogenesis in Gram-negative bacteria. Here we report a first biophysical characterization of this chaperone itself, which also possesses biotechnological potential in the production of recombinant proteins. Using cross-linking and gel filtration methods, we found that Skp forms a stable homo-trimer in solution. Following thermal denaturation, monitored by CD spectroscopy, this chaperone refolds with high efficiency but exhibits a pronounced hysteresis between the un- and refolding transitions. Using the recombinant protein equipped with the Strep-tag II at its N-terminus, suitable crystallization conditions for Skp were found. A first data set was collected to 2.60 A resolution.
authors.affiliation: Lehrstuhl für Biologische Chemie, Technische Universität München, D-85350 Freising-Weihenstephan, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Schlapschy
authors.forename: Monica K
authors.initials: MK
authors.lastname: Dommel
authors.forename: Kamyar
authors.initials: K
authors.lastname: Hadian
authors.forename: Marton
authors.initials: M
authors.lastname: Fogarasi
authors.forename: Ingo P
authors.initials: IP
authors.lastname: Korndörfer
authors.forename: Arne
authors.initials: A
authors.lastname: Skerra
mesh_terms: D000595:Amino Acid Sequence; D002942:Circular Dichroism; D003460:Crystallization; D018360:Crystallography, X-Ray; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics; D004926:Escherichia coli / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics; D006358:Hot Temperature; D018832:Molecular Chaperones / Q000737:chemistry* / Q000235:genetics; D008969:Molecular Sequence Data; D019897:Periplasm / Q000378:metabolism; D033903:Periplasmic Proteins / Q000737:chemistry* / Q000235:genetics; D011489:Protein Denaturation; D020673:Protein Renaturation; D020836:Protein Structure, Quaternary; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics
chemical_list: D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D018832:Molecular Chaperones; D033903:Periplasmic Proteins; D011994:Recombinant Proteins; C072721:Skp protein, E coli