title: Development of a tandem protein trans-splicing system based on native and engineered split inteins.
abstract: Protein trans-splicing involving naturally or artificially split inteins results in two polypeptides being linked together by a peptide bond. While this phenomenon has found a variety of applications in chemical biology and biotechnology, precious little is known about the molecular recognition events governing the initial fragment association step. In this study, fluorescence approaches have been used to measure the dissociation constant for the Ssp DnaE split intein interaction and to determine the on and off rates of fragment association. The DnaE fragments bind with low nanomolar affinity, and our data suggest that electrostatics make an important contribution to the very rapid association of the fragments at physiological pH. This information was used to develop a tandem trans-splicing system based on native and engineered split inteins. This novel system allows the one-pot assembly of three polypeptides under native conditions and can be performed in crude cell lysates. The technology should provide a convenient approach to the segmental isotopic or fluorogenic labeling of specific domains within the context of large multidomain proteins.
authors.affiliation: Laboratory of Synthetic Protein Chemistry, The Rockefeller University, 1230 York Avenue, New York, New York 10021, USA.
authors.forename: Jianxin
authors.initials: J
authors.lastname: Shi
authors.forename: Tom W
authors.initials: TW
authors.lastname: Muir
mesh_terms: D000595:Amino Acid Sequence; D004258:DNA Polymerase III / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D031541:Fluorescence Resonance Energy Transfer; D047668:Inteins; D007700:Kinetics; D008969:Molecular Sequence Data; D015202:Protein Engineering; D019154:Protein Splicing; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D046939:Synechocystis / Q000201:enzymology / Q000235:genetics; D013816:Thermodynamics; D020040:Trans-Splicing
chemical_list: D011993:Recombinant Fusion Proteins; C074904:DNA polymerase III, alpha subunit; D004258:DNA Polymerase III