| To investigate the amino acid sequence of tobacco Nt-GAD at the molecular level, the physical and chemical characteristics, structural domains and evolutionary trees of tobacco Nt-GAD amino acid sequence were analyzed using the tools of Protparam, Interpro, Blast, Muscle, Phyml and Treedin. The results showed that the isoelectric points of tobacco Nt-GAD members ranged between 5.5~6, and Nt-GAD1 exhibited the highest homology with Nt-GAD2 . In addition, Nt-GAD2 had the best heat resistance and Nt-GAD3 had the strongest stability. Tobacco Nt-GAD was classified within the pyridoxal phosphate-dependent decarboxylase family and the glutamate decarboxylase family, possessing the pyridoxal phosphate-dependent transferases homologous superfamily domain. A distinctive calmodulin domain was located at the C-terminal. Based on evolutionary tree analysis, tobacco Nt-GAD members were categorized into three groups.Among these group, tobacco Nt-GAD3 (group 1) is more prominent, whereas Nt-GAD2 (group 3) is more conservative, Nt-GAD1 and Nt-GAD4 constitute the second group. |
