DNA Folding Transition in Presence of Naphthylhydroxamic Acids as Revealed by Fluorescence Microscopic Single Molecule Observation Method.

Fluorescence microscopy is a field of growing applications in various fields as it can be used to study immunofluorescence,fluorescent proteins techniques, live-cell imaging and many more. The present investigation is based on this single molecule observation technique to observe the effect of N-arylhydroxamic acids on λ plasmid DNA and linear Bacteriophage T7 DNA. The compounds under present investigation include N-1-naphthyl-o-methylbenzohydroxamic acid,N-1-naphthyl-p-methylbenzohydroxamic acid, N-1-naphthyl ethoxy benzo hydroxamic acid, N-1-naphthylphenylacetohydroxamic acid and N-1-naphthyl valero hydroxamic acid. The hydrodynamic radius, RH of λ DNA and long-axis length, l of T7 DNA were determined from the direct observation of Brownian motion of the DNA molecules in the absence and presence of hydroxamic acids. Folding transition was observed for λ DNA as well as T7 DNA in the presence of naphthyl hydroxamic acids. N-1-naphthylvalerohydroxamic acid was found to be most effective.