Characterization of A DNA Fragment From Streptococcus Pyogenes With Nucleotide Homology to Gyrase a Active Site
A Thesis submitted to the Faculty of the Graduate School, Marquette University, in Partial Fulfillment of the Requirements for the Degree of Master of Science, Milwaukee, Wisconsin.
Abstract
The concept of a topologically active DNA molecule, as opposed to a static Watson and Crick double helix, emerged in the mid 1960’s and since then researchers have attempted to elucidate the function that topological changes might have for DNA. An essential enzyme in this topological activity is deoxyribonucleic acid topoisomerase II or ’’gyrase” as it is referred to in eubacteria and archaebacteria. Gyrase has been focused on not only because of its genetic regulation, but also because of its interaction with several groups of antibiotics, one of these being the quinolone family of antibiotics. The newer fluoroquinolones, such as ciprofloxacin, norfloxacin, and enoxacin, exhibit improved antimicrobial activity, however activity against gram-positive bacteria such as streptococci is still considerably less than that observed for gram-negative bacteria.