- 作者: 劉宣良
- 作者服務機構: Department of Chemical Engineering, National Taipei University of Technology, Taipei 106, Taiwan, R.O.C.
- 中文摘要: The stability and unfolding mechanism of the N-terminal b-hairpin of the [2Fe-2S] ferredoxin I from the blue-green alga Aphanothece sacrum in pure methanol, 40% (v/v) methanol-water, and pure water systems were investigated by 10 ns molecular dynamics simulations under periodic boundary conditions. The b-hairpin was mostly in its native-like state in pure methanol, whereas it unfolds dramatically following the ‘zip-up’mechanism when it was placed in pure water. Both interstrand and inside-turn hydrogen bonds account for the stability of the b-hairpin in its native-like conformation, whereas hydrophobic interactions among nonpolar side chains are responsible for maintaining its stable loop-like intermediate structures in 40% (v/v) methanol-water. Reducing solvent polarity seems to increase the stability of the b-hairpin in its native-like structure. Methanol is likely to mimic the partially hydrophobic environment around the N-terminal b-hairpin by the subsequent a-helix.
- 英文摘要: --
- 中文關鍵字: Blue-green alga Aphanothece sacrum; Methanol; Periodic boundary conditions; ‘Zip-up’ mechanism; Hydrogen bonds; Hydrophobic interactions; Polarity.
- 英文關鍵字: --