Three advances involving DNA in atomic force microscopy (AFM) are reported here. First a HEPES-Mg buffer has been used that improves the spreading of DNA and provides good DNA coverage with as little as 200-500 picograms per sample. Second, the new "tapping" mode has been used to improve the ease and resolution of AFM-imaging of DNA in air. Finally, AFM images are presented of single-stranded phi X-174 virion DNA with the gene 32 single-stranded binding protein. A summary of the current state of the field and of the methods for preparing and imaging DNA in the AFM is also presented.

Bacteriophage T4↗

PubMedDate not supplied

A novel minor groove binding reagent designed to serve as a "truck" to carry DNA modifying moieties into the major groove.

A site selective DNA minor groove binding tripyrrole peptide has been synthesized as a "truck" to place chemical functionalities into the major groove which are capable of physically modifying DNA, acting as catalysts to hydrolyze DNA, or effectively protecting DNA from various DNA modifying enzymes. The equilibrium dissociation constants for the binding of this peptide to an A3T3 dsDNA binding site have been determined to be nanomolar, and they are compared to the constants for other minor groove binding agents.

Base Sequence↗