Atomic force microscopy of single- and double-stranded DNA.
A method has been developed for imaging single-stranded DNA with the atomic force microscope (AFM). phi X174 single-stranded DNA in formaldehyde on mica can be imaged in the AFM under propanol or butanol or in air. Measured lengths of most molecules are on the order of 1 mu, although occasionally more extended molecules with lengths of 1.7 to 1.9 mu are seen. Single-stranded DNA in the AFM generally appears lumpier than double-stranded DNA, even when extended. Images of double-stranded lambda DNA in the AFM show more sharp kinks and bends than are typically observed in the electron microscope. Dense, aggregated fields of double-stranded plasmids can be converted by gentle rinsing with hot water to well spread fields.
Hansma
H G
HG
Department of Physics, University of California, Santa Barbara 93106.
Sinsheimer
R L
RL
Li
M Q
MQ
Hansma
P K
PK
D010582:Bacteriophage lambda / Q000737:chemistry* / Q000648:ultrastructure; D010584:Bacteriophage phi X 174 / Q000737:chemistry* / Q000648:ultrastructure; D004277:DNA, Single-Stranded / Q000648:ultrastructure*; D004279:DNA, Viral / Q000648:ultrastructure*; D016252:Microscopy, Scanning Tunneling; D009690:Nucleic Acid Conformation
D004277:DNA, Single-Stranded; D004279:DNA, Viral