来自Xenopus的一种新型内酶,可以识别alpha-helical二次结构
N M Resnick1, W L Maloy, H R Guy
1Division of Human Genetics Children's Hospital of Philadelphia, Pennsylvania.
Cell
|August 9, 1991
概括
的皮肤腺分泌一种金属蛋白酶,可以切割抗微生物的magainin. 这种新型的酶,magaininase,识别了特定的α-螺旋结构,而不仅仅是氨基酸序列.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 抗微生物是一种抗微生物.
背景情况:
- 在Xenopus laevis的皮肤腺体中,可以产生广泛的抗微生物药物.
- 这些被一个共同分泌的蛋白酶加工成更小的单元.
- 这种加工对于马加宁的抗菌活性至关重要.
研究的目的:
- 为了表征和净化负责加工magainin的内酶.
- 了解这种新型酶的基质特异性和催化机制.
- 为新发现的蛋白酶提出名称和分类.
主要方法:
- 从Xenopus皮肤中净化内酶以达到同质性.
- 酶的生物化学特征,包括大小和类型 (金属蛋白酶).
- 通过裂试验对基质特异性的分析.
主要成果:
- 该内酸酶被净化,并被确定为110kDa的金属蛋白酶.
- 该酶特别识别具有两性,阿尔法螺旋动机 (≥12残留物,疏水面) 的.
- 裂变发生在位于螺旋体疏水面上的氨酸残留物旁边.
结论:
- 已经确定了一种新型的内酶类,称为"magaininase".
- 这种酶基于二次结构 (α-螺旋) 而不是主要序列的分裂.
- 麦加尼纳酶在激活或调节抗微生物中发挥作用.
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