Atomic force microscopy of RecA--DNA complexes using a carbon nanotube tip.
We report high resolution images of RecA-double stranded (ds) DNA complexes obtained by atomic force microscopy (AFM). When a carbon nanotube (CNT) tip was used, AFM images visualized the 10-nm pitch of RecA-dsDNA complexes and RecA filaments as three-dimensional surface topography without reconstruction analysis. The depth of the notch between two pitches was less than 1 nm. When adsorbed on a soft surface covered with proteins, naked DNA, RecA monomers, RecA hexamers, and short RecA filaments were all clearly resolved in one image. The high resolution images with a CNT tip provided valuable information on the initiation process of RecA-dsDNA complex formation.
Umemura
K
K
Joint Research Center for Atom Technology, 1-1-4 Higashi, Tsukuba, Ibaraki 305-0046, Japan.
Komatsu
J
J
Uchihashi
T
T
Choi
N
N
Ikawa
S
S
Nishinaka
T
T
Shibata
T
T
Nakayama
Y
Y
Katsura
S
S
Mizuno
A
A
Tokumoto
H
H
Ishikawa
M
M
Kuroda
R
R
D004247:DNA / Q000737:chemistry / Q000648:ultrastructure*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000648:ultrastructure; D018625:Microscopy, Atomic Force / Q000295:instrumentation / Q000379:methods*; D011938:Rec A Recombinases / Q000737:chemistry / Q000648:ultrastructure*
D004268:DNA-Binding Proteins; D004247:DNA; D011938:Rec A Recombinases