Maras B, Valiante S, Chiaraluce R, Consalvi V, Politi L, De Rosa M, Bossa F, Scandurra R, Barra D
Dipartimento di Scienze Biochimiche A. Rossi Fanelli, Università La Sapienza, Roma, Italy.
J Protein Chem. 1994 Feb;13(2):253-9. doi: 10.1007/BF01891983.
The complete amino acid sequence of glutamate dehydrogenase from the archaebacterium Pyrococcus furiosus has been determined. The sequence was reconstructed by automated sequence analysis of peptides obtained after cleavage with cyanogen bromide, Asp-N endoproteinase, trypsin, or pepsin. The enzyme subunit is composed of 420 amino acid residues yielding a molecular mass of 47,122 D. In the recently determined primary structure of glutamate dehydrogenase from another thermophilic archaebacterium, Sulfolobus solfataricus, the presence of some methylated lysines was detected and the possible role of this posttranslational modification in enhancing the thermostability of the enzyme was discussed (Maras, B., Consalvi, V., Chiaraluce, R., Politi, L., De Rosa, M., Bossa, F., Scandurra, R., and Barra, D. (1992), Eur. J. Biochem. 203, 81-87). In the primary structure reported here, such posttranslational modification has not been found, indicating that the role of lysine methylation should be revisited. Comparison of the sequence of glutamate dehydrogenase from Pyrococcus furiosus with that of S. solfataricus shows a 43.7% similarity, thus indicating a common evolutionary pathway.
嗜热栖热菌谷氨酸脱氢酶的完整氨基酸序列已被确定。该序列是通过对用溴化氰、天冬氨酸蛋白酶N端内切酶、胰蛋白酶或胃蛋白酶切割后得到的肽段进行自动序列分析重建的。该酶亚基由420个氨基酸残基组成，分子量为47,122 D。在最近确定的另一种嗜热古细菌嗜热栖热菌谷氨酸脱氢酶的一级结构中，检测到一些甲基化赖氨酸的存在，并讨论了这种翻译后修饰在提高酶的热稳定性方面可能发挥的作用（马拉斯，B.，孔萨尔维，V.，基亚拉卢切，R.，波利蒂，L.，德罗萨，M.，博萨，F.，斯坎杜拉，R.，和巴拉，D.（1992年），欧洲生物化学杂志203，81 - 87）。在本文报道的一级结构中，未发现这种翻译后修饰，这表明赖氨酸甲基化的作用值得重新审视。嗜热栖热菌谷氨酸脱氢酶与嗜热栖热菌的序列比较显示相似度为43.7%，因此表明它们有共同的进化途径。
