title: Transglutaminase-mediated internal protein labeling with a designed peptide loop.
abstract: Post-translational internal protein labeling was explored through the insertion of a 13-mer peptidyl loop specifically recognized by microbial transglutaminase (MTG). The peptidyl loop included one lysine residue (abbreviated as the K-loop), and was designed and inserted into two different regions of the protein bacterial alkaline phosphatase (BAP). MTG-mediated selective labeling of a lysine residue in the K-loop was achieved with a functional Gln-donor substrate. Internal protein labeling in the vicinity of the active site of BAP (residues 91-93) markedly decreased the activity of the enzyme. Conversely, insertion of the K-loop at a site distal from the active site (residues 219-221) afforded site-specific and covalent internal protein labeling without impairing the activity of the enzyme.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Moto-oka, Fukuoka 819-0395, Japan.
authors.forename: Yutaro
authors.initials: Y
authors.lastname: Mori
authors.forename: Masahiro
authors.initials: M
authors.lastname: Goto
authors.forename: Noriho
authors.initials: N
authors.lastname: Kamiya
mesh_terms: D000469:Alkaline Phosphatase / Q000737:chemistry* / Q000235:genetics; D000595:Amino Acid Sequence; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry; D008239:Lysine / Q000737:chemistry*; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry*; D011499:Protein Processing, Post-Translational; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics; D011503:Transglutaminases / Q000737:chemistry*
chemical_list: D010455:Peptides; D011994:Recombinant Proteins; D011503:Transglutaminases; D000469:Alkaline Phosphatase; D016650:Fluorescein-5-isothiocyanate; D008239:Lysine