Download MendeleyThe novel amylase function of the carboxyl terminal domain of Amy63.
Sun, Y., Liu, G., Liu, G., Tang, H., Sun, C., Zhang, W., Chen, L.(2023) Biochem Biophys Res Commun 671: 10-17
- PubMed: 37290279
- DOI: https://doi.org/10.1016/j.bbrc.2023.05.071
- Primary Citation of Related Structures:
8JJM - PubMed Abstract:
α-amylase plays a crucial role in regulating metabolism and health by hydrolyzing of starch and glycogen. Despite comprehensive studies of this classic enzyme spanning over a century, the function of its carboxyl terminal domain (CTD) with a conserved eight β-strands is still not fully understood. Amy63, identified from a marine bacterium, was reported as a novel multifunctional enzyme with amylase, agarase and carrageenase activities. In this study, the crystal structure of Amy63 was determined at 1.8 Å resolution, revealing high conservation with some other amylases. Interestingly, the independent amylase activity of the carboxyl terminal domain of Amy63 (Amy63_CTD) was newly discovered by the plate-based assay and mass spectrometry. To date, the Amy63_CTD alone could be regarded as the smallest amylase subunit. Moreover, the significant amylase activity of Amy63_CTD was measured over a wide range of temperature and pH, with optimal activity at 60 °C and pH 7.5. The Small-angle X-ray scattering (SAXS) data showed that the high-order oligomeric assembly gradually formed with increasing concentration of Amy63_CTD, implying the novel catalytic mechanism as revealed by the assembly structure. Therefore, the discovery of the novel independent amylase activity of Amy63_CTD suggests a possible missing step or a new perspective in the complex catalytic process of Amy63 and other related α-amylases. This work may shed light on the design of nanozymes to process marine polysaccharides efficiently.
Organizational Affiliation:
Department of Medical Microbiology, Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China; Fudan University Pudong Medical Center, Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China; The Department of Systems Biology for Medicine, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China.
