Fast-scanning atomic force microscopy reveals the ATP/ADP-dependent conformational changes of GroEL.
In order to fold non-native proteins, chaperonin GroEL undergoes numerous conformational changes and GroES binding in the ATP-dependent reaction cycle. We constructed the real-time three-dimensional-observation system at high resolution using a newly developed fast-scanning atomic force microscope. Using this system, we visualized the GroES binding to and dissociation from individual GroEL with a lifetime of 6 s (k=0.17 s(-1)). We also caught ATP/ADP-induced open-closed conformational changes of individual GroEL in the absence of qGroES and substrate proteins. Namely, the ATP/ADP-bound GroEL can change its conformation 'from closed to open' without additional ATP hydrolysis. Furthermore, the lifetime of open conformation in the presence of ADP ( approximately 1.0 s) was apparently lower than those of ATP and ATP-analogs (2-3 s), meaning that ADP-bound open-form is structurally less stable than ATP-bound open-form. These results indicate that GroEL has at least two distinct open-conformations in the presence of nucleotide; ATP-bound prehydrolysis open-form and ADP-bound open-form, and the ATP hydrolysis in open-form destabilizes its open-conformation and induces the 'from open to closed' conformational change of GroEL.
Yokokawa
Masatoshi
M
Laboratory of Plasma Membrane and Nuclear Signaling, Kyoto University Graduate School of Biostudies, Kyoto, Japan. yokokawa@lif.kyoto-u.ac.jp
Wada
Chieko
C
Ando
Toshio
T
Sakai
Nobuaki
N
Yagi
Akira
A
Yoshimura
Shige H
SH
Takeyasu
Kunio
K
D000244:Adenosine Diphosphate / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism*; D018835:Chaperonin 10 / Q000648:ultrastructure; D018834:Chaperonin 60 / Q000737:chemistry* / Q000648:ultrastructure*; D004926:Escherichia coli / Q000737:chemistry*; D007700:Kinetics; D018625:Microscopy, Atomic Force / Q000379:methods*; D008954:Models, Biological; D008958:Models, Molecular; D011485:Protein Binding; D011487:Protein Conformation; D012996:Solutions
D018835:Chaperonin 10; D018834:Chaperonin 60; D012996:Solutions; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate