title: Lysine and polyamines are substrates for transglutamination of Rho by the Bordetella dermonecrotic toxin.
abstract: Bordetella dermonecrotic toxin (DNT) catalyzes the transglutamination of glutamine-63/61 of Rho GTPases, thereby constitutively activating Rho proteins. Here we identified second substrates for transglutamination of RhoA by DNT. The enzymatically active fragment of DNT (residues 1136 to 1451, DeltaDNT) induced the incorporation of L-[(14)C]lysine in RhoA in a concentration-dependent manner. Also, Rac and Cdc42, but not Ras, were transglutaminated with lysine by DeltaDNT. Transglutamination of the GTPase with L-lysine inhibited intrinsic and Rho-GAP-stimulated GTP hydrolysis of RhoA. In contrast to lysine, treatment of RhoA with alanine, arginine, and glutamine were not able to substitute for lysine in the transglutamination reaction. DNT increased the incorporation of L-[(14)C]lysine into embryonic bovine lung cells. Microinjection of GST-RhoA together with the enzymatically active DNT fragment into Xenopus oocytes, subsequent affinity purification of modified GST-RhoA, and mass spectrometry identified attachment of putrescine or spermidine at glutamine-63 of RhoA. A comparison of putrescine, spermidine, and lysine as substrates for DNT-induced transglutamination of RhoA revealed that lysine is a preferred second substrate at least in vitro.
authors.affiliation: Institut für Experimentelle und Klinische Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, D-79104 Freiburg, Germany. gudschmi@uni-freiburg.de
authors.forename: G
authors.initials: G
authors.lastname: Schmidt
authors.forename: U M
authors.initials: UM
authors.lastname: Goehring
authors.forename: J
authors.initials: J
authors.lastname: Schirmer
authors.forename: S
authors.initials: S
authors.lastname: Uttenweiler-Joseph
authors.forename: M
authors.initials: M
authors.lastname: Wilm
authors.forename: M
authors.initials: M
authors.lastname: Lohmann
authors.forename: A
authors.initials: A
authors.lastname: Giese
authors.forename: G
authors.initials: G
authors.lastname: Schmalzing
authors.forename: K
authors.initials: K
authors.lastname: Aktories
mesh_terms: D000818:Animals; D001427:Bacterial Toxins / Q000378:metabolism*; D001884:Bordetella / Q000201:enzymology*; D003432:Cross-Linking Reagents; D008239:Lysine / Q000378:metabolism; D008845:Microinjections; D009865:Oocytes; D011073:Polyamines / Q000378:metabolism; D011700:Putrescine / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013095:Spermidine / Q000378:metabolism; D013379:Substrate Specificity; D011503:Transglutaminases / Q000378:metabolism*; D010566:Virulence Factors, Bordetella; D014981:Xenopus; D020741:rho GTP-Binding Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D020742:rhoA GTP-Binding Protein / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism
chemical_list: D001427:Bacterial Toxins; D003432:Cross-Linking Reagents; D011073:Polyamines; D011993:Recombinant Fusion Proteins; D010566:Virulence Factors, Bordetella; C060969:dermonecrotic toxin, Bordetella; D011503:Transglutaminases; D020741:rho GTP-Binding Proteins; D020742:rhoA GTP-Binding Protein; D008239:Lysine; D013095:Spermidine; D011700:Putrescine