Mareček Filip, Møller Marie Sofie, Svensson Birte, Janeček Štefan
Department of Biology, Faculty of Natural Sciences, University of SS. Cyril and Methodius, Nám. J. Herdu 2, 91701 Trnava, Slovakia.
Laboratory of Protein Evolution, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 21, 84551 Bratislava, Slovakia.
3 Biotech. 2021 May;11(5):229. doi: 10.1007/s13205-021-02787-8. Epub 2021 Apr 21.
The family GH77 contains 4-α-glucanotransferase acting on α-1,4-glucans, known as amylomaltase in prokaryotes and disproportionating enzyme in plants. A group of bacterial GH77 members, represented by amylomaltases from and , possesses an N-terminal extension that forms a distinct immunoglobulin-like fold domain, of which no function has been identified. Here, in silico analysis of 100 selected sequences of N-terminal domain homologues disclosed several well-conserved residues, among which Tyr108 ( amylomaltase numbering) may be involved in α-glucan binding. These N-terminal domains, therefore, may represent a new type of starch-binding domain and define a new CBM family. This hypothesis is supported by docking of maltooligosaccharides to the N-terminal domain in amylomaltases, representing the four clusters of the phylogenetic tree.
The online version contains supplementary material available at 10.1007/s13205-021-02787-8.
GH77家族包含作用于α-1,4-葡聚糖的4-α-葡聚糖转移酶，在原核生物中称为淀粉麦芽糖酶，在植物中称为歧化酶。一组以来自[具体物种1]和[具体物种2]的淀粉麦芽糖酶为代表的细菌GH77成员，具有一个N端延伸，形成一个独特的免疫球蛋白样折叠结构域，其功能尚未确定。在此，对100个选定的N端结构域同源物序列进行的计算机分析揭示了几个保守性良好的残基，其中Tyr108（淀粉麦芽糖酶编号）可能参与α-葡聚糖结合。因此，这些N端结构域可能代表一种新型的淀粉结合结构域，并定义了一个新的碳水化合物结合模块（CBM）家族。这一假设得到了麦芽寡糖与淀粉麦芽糖酶中N端结构域对接的支持，淀粉麦芽糖酶代表了系统发育树的四个簇。
在线版本包含可在10.1007/s13205-021-02787-8获取的补充材料。
