Barriuso Jorge, Martínez María Jesús
Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Department of Environmental Biology, Ramiro de Maeztu 9, Madrid, E-28040, Spain.
BMC Genomics. 2017 Jan 3;18(1):12. doi: 10.1186/s12864-016-3419-2.
Fungal "Versatile carboxylic ester hydrolases" are enzymes with great biotechnological interest. Here we carried out a bioinformatic screening to find these proteins in genomes from Agaricales, by means of searching for conserved motifs, sequence and phylogenetic analysis, and three-dimensional modeling. Moreover, we reconstructed the molecular evolution of these enzymes along the time by inferring and analyzing the sequence of ancestral intermediate forms.
The properties of the ancestral candidates are discussed on the basis of their three-dimensional structural models, the hydrophobicity of the lid, and the substrate binding intramolecular tunnel, revealing all of them featured properties of these enzymes. The evolutionary history of the putative lipases revealed an increase on the length and hydrophobicity of the lid region, as well as in the size of the substrate binding pocket, during evolution time. These facts suggest the enzymes' specialization towards certain substrates and their subsequent loss of promiscuity.
These results bring to light the presence of different pools of lipases in fungi with different habitats and life styles. Despite the consistency of the data gathered from reconstruction of ancestral sequences, the heterologous expression of some of these candidates would be essential to corroborate enzymes' activities.
真菌“多功能羧酸酯水解酶”是具有重大生物技术意义的酶。在此,我们开展了一项生物信息学筛选,通过寻找保守基序、进行序列和系统发育分析以及三维建模,在伞菌目的基因组中寻找这些蛋白质。此外,我们通过推断和分析祖先中间形式的序列,重建了这些酶随时间的分子进化。
根据祖先候选酶的三维结构模型、盖子的疏水性以及底物结合分子内隧道,对其性质进行了讨论,结果表明它们均具有这些酶的特征性质。推测的脂肪酶的进化历史显示,在进化过程中,盖子区域的长度和疏水性以及底物结合口袋的大小均有所增加。这些事实表明这些酶对某些底物的专一化以及随后混杂性的丧失。
这些结果揭示了在具有不同栖息地和生活方式的真菌中存在不同的脂肪酶库。尽管从祖先序列重建中收集的数据具有一致性,但对其中一些候选酶进行异源表达对于证实酶的活性至关重要。