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Full-Text Articles in Biology
Scanning Tunneling Microscope Images Of Adenine And Thymine At Atomic Resolution, M. J. Allen, M. Balooch, S. Subbiah, R. J. Tench, W. Siekhaus, R. Balhorn
Scanning Tunneling Microscope Images Of Adenine And Thymine At Atomic Resolution, M. J. Allen, M. Balooch, S. Subbiah, R. J. Tench, W. Siekhaus, R. Balhorn
Scanning Microscopy
The scanning tunneling microscope has been used to obtain images of DNA that reveal its major and minor grooves and the direction of helical coiling, but sufficient resolution has not yet been achieved to identify its bases. To determine if this technology is capable of identifying individual DNA bases, we have examined the molecular arrangements of adenine and thymine attached to the basal plane of highly oriented pyrolytic graphite. Both molecules form highly organized lattices following deposition on heated graphite. Lattice dimensions, structural periodicities, and the epitaxy of adenine and thymine molecules with respect to the basal plane of graphite …
High-Resolution, Real-Space Imaging Of Conformational Structures Of Poly-L-Proline Helixes, N. J. Zheng, G. Rau, C. F. Hazlewood, C. Rau
High-Resolution, Real-Space Imaging Of Conformational Structures Of Poly-L-Proline Helixes, N. J. Zheng, G. Rau, C. F. Hazlewood, C. Rau
Scanning Microscopy
In 1954, Edsall postulated that the imino-acid proline, which is a frequently found constituent of protein molecules, is a key determinant to the three-dimensional architecture of proteins. It not only should play a fundamental role in stabilizing helical structures of polypeptides, it should allow for sharp bends and even for a complete reversal of the direction of a helix looping back on itself. No direct evidence has yet been published to prove this prediction. Using scanning tunneling microscopy, we have presented high-resolution, real-space images of two conformations of poly-L-proline, where one structure clearly exhibits the predicted 180° back-folding behavior. The …
Scanning Tunneling Microscopy Imaging Of Synthetic Oligonucleotides And Oligonucleotide-Metal Complexes, Yun Kim, Charles M. Lieber
Scanning Tunneling Microscopy Imaging Of Synthetic Oligonucleotides And Oligonucleotide-Metal Complexes, Yun Kim, Charles M. Lieber
Scanning Microscopy
Scanning tunneling microscopy (STM) has been used to image 12-and 24-base pair (bp) synthetic oligonucleotide duplexes alone or with intercalatively-bound metal complexes with submolecular resolution. The sizes of the 12-and 24-bp oligonucleotides determined from STM images are close to expected values, and images of isolated duplexes resolve the two nucleotide strands of these molecules. The variation of duplex size in our images demonstrates that these features are not due to surface artifacts. In addition, images of the 12-bp duplex in the presence of bis(9, 10-phenanthrenequinone diimine)(2, 2'-bipyridyl) rhodium(III) exhibit a new structural feature at 14 ± 2 Å from the …