Chu F K, Takase K, Guarino D, Maley F
Biochemistry. 1985 Oct 22;24(22):6125-32. doi: 10.1021/bi00343a014.
It has been shown by genetic analysis that the external and internal invertases from Saccharomyces cerevisiae share a common structural gene [Taussig, R., & Carlson, M. (1983) Nucleic Acids Res. 11, 1943-1954]. However, the only amino acid composition of these two forms of invertase reported to date has revealed extensive differences [Gascon, S., Neumann, N.P., & Lampen, J.O. (1968) J. Biol. Chem. 243, 1573-1577]. We have found from amino acid analyses of both enzymes and sodium dodecyl sulfate-polyacrylamide gel analysis of their cyanogen bromide peptides that they are most likely identical in their amino acid sequence. However, the invertases exhibit dramatically different physical properties, particularly in their stability. The most striking difference was in their renaturation following guanidine treatment where it was shown that inactivated external invertase could be renatured completely. Endo-beta-N-acetylglucosaminidase H treated external invertase was restored to 40% of its original activity while internal invertase remained completely inactive. The observed differences may be attributed to the presence and absence of the oligosaccharide moiety in the external and internal invertases, respectively.
遗传分析表明，酿酒酵母的外切和内切蔗糖酶共享一个共同的结构基因[Taussig, R., & Carlson, M. (1983) Nucleic Acids Res. 11, 1943 - 1954]。然而，迄今为止报道的这两种形式蔗糖酶的唯一氨基酸组成显示出广泛差异[Gascon, S., Neumann, N.P., & Lampen, J.O. (1968) J. Biol. Chem. 243, 1573 - 1577]。我们通过对两种酶的氨基酸分析以及对它们的溴化氰肽进行十二烷基硫酸钠 - 聚丙烯酰胺凝胶分析发现，它们的氨基酸序列很可能是相同的。然而，这两种蔗糖酶表现出显著不同的物理性质，特别是在稳定性方面。最显著的差异在于它们在胍处理后的复性情况，结果表明失活的外切蔗糖酶可以完全复性。经内切 - β - N - 乙酰葡糖胺糖苷酶H处理的外切蔗糖酶恢复到其原始活性的40%，而内切蔗糖酶仍然完全无活性。观察到的差异可能分别归因于外切和内切蔗糖酶中寡糖部分的存在和缺失。
