Molecular Dynamics Simulations to Determine of the Optimum Length and Type O-Glycosylation in the Linker Domain of Glucoamylase from Aspergillus awamori

以分子型態模擬研究來自Aspergillus awamori菌種之Glucoamylase之連結區最適之O型醣化長度及鍵結型態

劉宣良(Hsuan-Liang Liu)

《Journal of the Chinese Institute of Chemical Engineers》 34卷6期 (2003/11) Pp. 655-660

https://doi.org/10.6967/JCICE.200311.0655

摘要

在本研究中，我們以10 ns之分子動態模擬研究來自Aspergillus awamori菌種之 glucoamylase之連結區最適之O型醣化長度及鍵結型態。在未將糖鍵結於連結區中的Thr及Ser氨基酸時，其N- 端到 C- 端中的線性長度會在105及126 Å間快速變動。在實際的生理條件下，甘露糖比半乳糖更容易以O型醣化型態結於Ser及Thr氨基酸上，在pH4.5及330K時，平均5個甘露糖會鍵結於Ser及Thr上導致此連結區的平均長度為95 Å。連結區中16個Thr氨基酸上的羥羰基氧原子與第一個甘露糖上之質子所形成的氫鍵能穩定O型醣化的型態。

並列摘要

In this study, 10 ns molecular dynamics simulations were conducted to determine the optimum length and type of O-glycosylation in the linker domain of glucoamylase from Aspergillus awamori. The linear distance between the N- and C-termini of the linker domain fluctuated rapidly between 105 and 126 Å without adding sugars onto the Thr and Ser residues. Mannose was found to be more favorable to be O-linked to the Ser and Thr residues than galactose under the realistic biophysical conditions. Averagely 5 mannose residues O-linked to the Thr and Ser residues results in the averaged linear distance of 95 Å between the N- and C-termini at pH 4.5 and 330K. Hydrogen bonds between the carbony1 oxygen of the 16 Thr residues in the linker domain and the proton in the +1 mannose contribute to stabilizing the O-glycosylated motif.

並列關鍵字

molecular dynamics simulations ； O-glycosylation ； glucoamylase ； mannose ； galactose