Driving force behind adsorption-induced protein unfolding: a time-resolved X-ray reflectivity study on lysozyme adsorbed at an air/water interface.
Time-resolved X-ray reflectivity measurements for lysozyme (LSZ) adsorbed at an air/water interface were performed to study the mechanism of adsorption-induced protein unfolding. The time dependence of the density profile at the air/water interface revealed that the molecular conformation changed significantly during adsorption. Taking into account previous work using Fourier transform infrared (FTIR) spectroscopy, we propose that the LSZ molecules initially adsorbed on the air/water interface have a flat unfolded structure, forming antiparallel beta-sheets as a result of hydrophobic interactions with the gas phase. In contrast, as adsorption continues, a second layer forms in which the molecules have a very loose structure having random coils as a result of hydrophilic interactions with the hydrophilic groups that protrude from the first layer.
Yano
Yohko F
YF
Synchrotron Light Life Science Center, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu-shi, Shiga 525-8577, Japan. y-yano@fc.ritsumei.ac.jp
Uruga
Tomoya
T
Tanida
Hajime
H
Toyokawa
Hidenori
H
Terada
Yasuko
Y
Takagaki
Masafumi
M
Yamada
Hironari
H
D000327:Adsorption; D000388:Air; D007700:Kinetics; D009113:Muramidase / Q000737:chemistry*; D011489:Protein Denaturation; D013499:Surface Properties; D014867:Water; D014965:X-Rays
D014867:Water; D009113:Muramidase