title: New fluorescent substrates of microbial transglutaminase and its application to peptide tag-directed covalent protein labeling.
abstract: Transglutaminase (TGase) is an enzyme that catalyzes the post-translational covalent cross-linking of Gln- and Lys-containing peptides and/or proteins according to its substrate specificity. We have recently designed a variety of Gln-donor fluorescent substrates of microbial transglutaminase (MTG) from Streptomyces mobaraensis and evaluated their potential use in MTG-mediated covalent protein labeling. The newly designed substrates are based on the relatively broad substrate recognition of MTG for the substitution of the N-terminal group of a conventional TGase substrate, benzyloxycarbonyl-L-glutaminylglycine (Z-QG). It is revealed that MTG is capable of accepting a diverse range of fluorophores in place of the N-terminal moiety of Z-QG when linked via a suitable linker. Here, we show the potential utility of a new fluorescent substrate for peptide tag-directed covalent protein labeling by employing fluorescein-4-isothiocyanate-β-Ala-QG as a model Gln-donor substrate for MTG.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, Fukuoka, Japan. nori_kamiya@mail.cstm.kyushu-u.ac.jp
authors.forename: Noriho
authors.initials: N
authors.lastname: Kamiya
authors.forename: Hiroki
authors.initials: H
authors.lastname: Abe
mesh_terms: D000469:Alkaline Phosphatase / Q000737:chemistry / Q000235:genetics; D000595:Amino Acid Sequence; D055162:Biocatalysis; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics; D005449:Fluorenes / Q000737:chemistry; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D005822:Genetic Vectors / Q000235:genetics; D005973:Glutamine / Q000737:chemistry; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000737:chemistry* / Q000235:genetics; D013194:Staining and Labeling / Q000379:methods*; D013302:Streptomyces / Q000201:enzymology*; D013379:Substrate Specificity; D011503:Transglutaminases / Q000378:metabolism*
chemical_list: C496789:9-fluorenylmethoxycarbonyl; D005449:Fluorenes; D005456:Fluorescent Dyes; D010455:Peptides; D011993:Recombinant Fusion Proteins; D005973:Glutamine; D011503:Transglutaminases; D000469:Alkaline Phosphatase; D016650:Fluorescein-5-isothiocyanate