Bork P, Koonin E V
European Molecular Biology Laboratory, Heidelberg, Germany.
Protein Sci. 1994 Aug;3(8):1344-6. doi: 10.1002/pro.5560030821.
Using computer methods for database search and multiple alignment, statistically significant sequence similarities were identified between several nitrilases with distinct substrate specificity, cyanide hydratases, aliphatic amidases, beta-alanine synthase, and a few other proteins with unknown molecular function. All these proteins appear to be involved in the reduction of organic nitrogen compounds and ammonia production. Sequence conservation over the entire length, as well as the similarity in the reactions catalyzed by the known enzymes in this family, points to a common catalytic mechanism. The new family of enzymes is characterized by several conserved motifs, one of which contains an invariant cysteine that is part of the catalytic site in nitrilases. Another highly conserved motif includes an invariant glutamic acid that might also be involved in catalysis.
通过计算机数据库搜索和多重比对方法，在几种具有不同底物特异性的腈水解酶、氰化物水合酶、脂肪族酰胺酶、β-丙氨酸合酶以及其他一些分子功能未知的蛋白质之间，发现了具有统计学意义的序列相似性。所有这些蛋白质似乎都参与有机氮化合物的还原和氨的生成。该家族已知酶的整个序列的保守性以及所催化反应的相似性，表明存在共同的催化机制。这个新的酶家族具有几个保守基序，其中一个包含一个不变的半胱氨酸，它是腈水解酶催化位点的一部分。另一个高度保守的基序包含一个不变的谷氨酸，它可能也参与催化作用。
