College of Marine Sciences, HuaiHai Institute of Technology, Lianyungang, People's Republic of China.
J Basic Microbiol. 2013 Mar;53(3):231-9. doi: 10.1002/jobm.201100530. Epub 2012 Jun 26.
Thermostable amylopullulanase (TAPU) is valuable in starch saccharification industry for its capability to catalyze both α-1,4 and α-1,6 glucosidic bonds under the industrial starch liquefication condition. The majority of TAPUs belong to glycoside hydrolase family 57 (GH57). In this study, we performed a phylogenetic analysis of GH57 amylopullulanase (APU) based on the highly conserved DOMON_glucodextranase_like (DDL) domain and classified APUs according to their multidomain architectures, phylogenetic analysis and enzymatic characters. This study revealed that amylopullulanase, pullulanase, andα-amylase had passed through a long joint evolution process, in which DDL played an important role. The phylogenetic analysis of DDL domain showed that the GH57 APU is directly sharing a common ancestor with pullulanase, and the DDL domains in some species undergo evolution scenarios such as domain duplication and recombination.
耐热性直链淀粉/支链淀粉糊精酶（TAPU）在淀粉糖化工业中具有重要价值，因为它能够在工业淀粉液化条件下催化α-1,4 和 α-1,6 糖苷键。大多数 TAPUs 属于糖苷水解酶家族 57（GH57）。在这项研究中，我们根据高度保守的 DOMON_glucodextranase_like（DDL）结构域对 GH57 直链淀粉/支链淀粉糊精酶（APU）进行了系统发育分析，并根据其多结构域结构、系统发育分析和酶学特性对 APU 进行了分类。本研究表明，直链淀粉酶、支链淀粉酶和α-淀粉酶经历了一个漫长的共同进化过程，其中 DDL 发挥了重要作用。DDL 结构域的系统发育分析表明，GH57 APU 与支链淀粉酶直接共享一个共同的祖先，并且某些物种的 DDL 结构域经历了结构域复制和重组等进化情景。
