title: Protein splicing: an analysis of the branched intermediate and its resolution by succinimide formation.
abstract: Protein splicing involves the excision of an internal domain from a precursor protein and the ligation of the external domains so as to generate two new proteins. Study of this process has recently been facilitated by the isolation of a precursor and a branched intermediate from a thermophilic protein splicing element expressed in a foreign protein context. Two aspects of protein splicing are examined in this paper. We demonstrate a succinimide at the C-terminus of the spliced internal protein, implicating cyclization of asparagine in resolution of the branched intermediate, and we identify an alkali-labile bond in the branched intermediate. A revised protein splicing model based on these experimental results is presented.
authors.affiliation: New England Biolabs, Inc., Beverly, MA 01915.
authors.forename: M Q
authors.initials: MQ
authors.lastname: Xu
authors.forename: D G
authors.initials: DG
authors.lastname: Comb
authors.forename: H
authors.initials: H
authors.lastname: Paulus
authors.forename: C J
authors.initials: CJ
authors.lastname: Noren
authors.forename: Y
authors.initials: Y
authors.lastname: Shao
authors.forename: F B
authors.initials: FB
authors.lastname: Perler
mesh_terms: D000468:Alkalies; D000595:Amino Acid Sequence; D001483:Base Sequence; D017124:Conserved Sequence; D017931:DNA Primers; D008969:Molecular Sequence Data; D011499:Protein Processing, Post-Translational; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013388:Succinimides / Q000378:metabolism*
chemical_list: D000468:Alkalies; D017931:DNA Primers; D011506:Proteins; D013388:Succinimides; C032620:succinimide