Image analysis by electron microscopy of two-dimensional crystals developed on a mercury surface of chaperonin from Thermus thermophilus.
Two-dimensional crystals of functional chaperonin molecules, which are protein complexes of cpn60 and cpn10, isolated from Thermus thermophilus were prepared on a mercury surface under oxygen atmosphere and were observed by electron microscope after transferring them to carbon coated specimen grids. The crystals showed the hexagonal lattice with unit cell dimensions of a = b = 12.4 nm and gamma = 120 degrees. The averaged image at a 3 nm resolution of the chaperonin has a doughnut-like shape which has seven peripheral masses and a central cavity. Preincubation of the chaperonin with MgATP changed the mobility in non-denaturating PAGE but did not cause distinguishable change of shape. The location of cpn10 in the chaperonin molecule is discussed.
Department of Life Science, Tokyo Institute of Technology, Kanagawa.
N
N
Ishii
H
H
Taguchi
M
M
Yoshida
H
H
Yoshimura
K
K
Nagayama
D001426:Bacterial Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000648:ultrastructure; D018833:Chaperonins; D003460:Crystallization; D008628:Mercury; D008854:Microscopy, Electron; D008970:Molecular Weight; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000648:ultrastructure*; D016963:Thermus thermophilus / Q000737:chemistry*
D001426:Bacterial Proteins; D011506:Proteins; D018833:Chaperonins; D008628:Mercury