Biochemistry, Biophysics, and Structural Biology Commons^™

Oxidative Dna Damage Modulates Genome And Epigenome Integrity Via Base Excision Repair, Pawlos S. Tsegay

FIU Electronic Theses and Dissertations

Oxidative DNA damage is one of the leading causes of genome instability, cell death, and diseases. It is repaired by DNA base excision repair (BER), during which repair and translesion DNA polymerases may incorporate damaged nucleotides and mediate RNA-guided DNA repair induced by DNA replication and gene transcription leading to the modulation of genome stability. On the other hand, oxidative DNA damage may result in cellular epigenetic responses to regulate DNA repair, altering genome stability and integrity. In this dissertation, we revealed the molecular mechanisms underlying the misincorporation of oxidized nucleotides, 5′,8-cyclo-2-cyclodeoxyadenosine (cdA) and RNA-guided base lesion repair mediated by …

High And Low Toxin Producing Strains Of Karenia Brevis Differ Significantly In The Redox Proteome, Lipid Profiles, And Xanthophyll Cycle Pigments, Ricardo Colon

FIU Electronic Theses and Dissertations

The dinoflagellate Karenia brevis, blooms annually in the Gulf of Mexico, producing a suite of neurotoxins known as the brevetoxins. The cellular toxin content of K. brevis, however, is highly variable between or even within strains. I investigated biochemical differences between high (KbHT) and low (KbLT) toxin producing cultures both derived from the Wilson strain, related to energy-dependent quenching (qE) by photosystem II, and the content of reduced thiols of the proteome. By characterizing the xanthophyll content of the two strains I was able to determine that KbLT performs qE inconsistently. To investigate the …

Type I Topoisomerases As Potential Targets For Therapeutics, Ahmed Seddek

FIU Electronic Theses and Dissertations

DNA topoisomerases are universal enzymes that control the topological features of DNA in all forms of life. This study aims to find potential inhibitors of some of the DNA topoisomerases in bacteria and humans that can be developed into potential therapeutics.

The first aim of this study is to find potential inhibitors of bacterial topoisomerase I that can be developed into antibiotics. There is an urgent need to develop novel antibiotics to overcome the world-wide health crisis of antimicrobial resistance. Virtual screening and biochemical assays were combined to screen thousands of compounds for potential inhibitors of bacterial topoisomerase I. NSC76027 …