title: Isolation of Type III Secretion System Needle Complexes by Shearing.
abstract: Type III secretion (T3S) needle proteins are essential for the pathogenesis of many gram-negative bacteria. The needle component of the T3S system serves as the conduit for the translocation of effector proteins from the cytoplasm of many gram-negative bacteria into their target eukaryotic cells. Despite substantial advances that have been made in their characterization, a lot is still unknown about their interactions with other T3S system proteins and their roles in modulating host immune responses during infections. Critical to achieving this knowledge is the ability to isolate these needle proteins in their stable, native form. In this chapter, we describe a modified, streamlined isolation strategy for native forms of these T3S system needle proteins. We also present assays to detect the presence and quantification of these needle proteins.
authors.affiliation: Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, USA.
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Nilles
authors.affiliation: Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, USA.
authors.forename: Danielle L Jessen
authors.initials: DL
authors.lastname: Condry
authors.affiliation: Department of Microbiology, University of Chicago, 920 East 59th St., Chicago, IL, 60637, USA. poseiowusu@uchicago.edu.
authors.forename: Patrick
authors.initials: P
authors.lastname: Osei-Owusu
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D015153:Blotting, Western; D004586:Electrophoresis; D006090:Gram-Negative Bacteria / Q000378:metabolism*; D046912:Multiprotein Complexes / Q000302:isolation & purification* / Q000378:metabolism*; D000069296:Type III Secretion Systems / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D046912:Multiprotein Complexes; D000069296:Type III Secretion Systems
keywords: Needle complex; Purification of needle proteins; Translocon; Type III secretion needle proteins; Type III secretion system