Fraij B M
Department of Biochemistry & Molecular Biology, Oklahoma State University, Stillwater 74078-3035, USA.
Biochem Biophys Res Commun. 1996 Jan 5;218(1):45-9. doi: 10.1006/bbrc.1996.0009.
Human tissue transglutaminase homologue cDNA was expressed in E. coli to analyze the catalytic characteristics. The transglutaminase homologue was purified by immunoaffinity chromatography. Specificity of GTP binding by the homologue was demonstrated by photoaffinity labeling in the absence or presence of GTP-gamma-S. The homologue had GTPase activity with an apparent Km value of 1.8 microM, several-fold lower than the reported Km values for the native tissue transglutaminase. GTPase activity was inhibited by guanine nucleotides in order GTP-gamma-S > GDP > GMP. The higher GTPase activity of the homologue may be related to the signaling events function.
人组织转谷氨酰胺酶同源物cDNA在大肠杆菌中表达以分析其催化特性。转谷氨酰胺酶同源物通过免疫亲和层析进行纯化。通过在存在或不存在GTP-γ-S的情况下进行光亲和标记来证明同源物与GTP结合的特异性。该同源物具有GTP酶活性，表观Km值为1.8μM，比报道的天然组织转谷氨酰胺酶的Km值低几倍。GTP酶活性被鸟嘌呤核苷酸以GTP-γ-S> GDP> GMP的顺序抑制。同源物较高的GTP酶活性可能与信号转导事件功能有关。
