Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education & Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, PR China.
Qilu Institute of Technology, Shandong 250200, PR China.
Int J Biol Macromol. 2024 Oct;278(Pt 1):134182. doi: 10.1016/j.ijbiomac.2024.134182. Epub 2024 Jul 26.
α-Amylases and glucoamylases play a crucial role in starch degradation for various industrial applications. Further exploration of novel α-amylases and glucoamylases with diverse enzymatic characteristics is necessary. In this study, metagenomics analysis revealed a high abundance of these enzymes in the microorganisms of Daqu and Pu-erh tea, identifying 271 glucoamylases and 232 α-amylases with significant sequence identity to known enzymes. Functional studies indicated that these enzymes have broad optimal temperatures (30 °C to 70 °C) and acidic or neutral pH optima. Additionally, two novel low-temperature glucoamylases and one novel low-temperature α-amylases were characterized, demonstrating potential for use in industries operating under low temperature conditions. Further analysis suggested that fewer molecular interactions and more flexible coli regions may contribute to their high activity at low temperatures. In summary, this study not only highlights the feasibility of exploring enzymes through metagenomic approaches, but also presents a library of novel and diverse α-amylases and glucoamylases for potential industrial applications.
α-淀粉酶和葡萄糖淀粉酶在各种工业应用中对淀粉的降解起着至关重要的作用。进一步探索具有不同酶学特性的新型α-淀粉酶和葡萄糖淀粉酶是必要的。在这项研究中，宏基因组分析表明，大曲和普洱茶微生物中这些酶的丰度很高，鉴定出 271 种葡萄糖淀粉酶和 232 种与已知酶具有显著序列同一性的α-淀粉酶。功能研究表明，这些酶具有广泛的最佳温度（30°C 至 70°C）和酸性或中性 pH 最佳值。此外，还对两种新型低温葡萄糖淀粉酶和一种新型低温α-淀粉酶进行了表征，证明它们在低温条件下的工业应用具有潜力。进一步的分析表明，较少的分子相互作用和更灵活的coli 区域可能有助于它们在低温下的高活性。总之，本研究不仅强调了通过宏基因组方法探索酶的可行性，还为潜在的工业应用提供了一系列新型和多样化的α-淀粉酶和葡萄糖淀粉酶。
