Biochemistry Commons^™

Developing A Biocatalytic Toolbox To Aid In Understanding Nucleoside Antibiotics, Jasmine Brianna Woods

Theses and Dissertations--Pharmacy

Antibiotic resistance happens when bacteria develop the ability to survive medications that normally terminate them. Instead, these super germs are able to survive in the body and produce a community of antibiotic resistance germs which can cause human fatalities. It is important to discover and develop new compounds and molecules that will improve this clinical obstacle. This research focused on analyzing the biosynthesis that incorporates distinctive chemical characteristic of various nucleoside antibiotics, ß-hydroxy amino acids and α-methyl-amino acids. ß-hydroxy amino acids and α-methyl-amino acids are considered an important class of industrially useful compounds, particularly for pharmaceutical development, and are found …

Toward An Enzyme-Coupled, Bioorthogonal Platform For Methyltransferases: Probing The Specificity Of Methionine Adenosyltransferases, Tyler D. Huber

Theses and Dissertations--Pharmacy

Methyl group transfer from S-adenosyl-l-methionine (AdoMet) to various substrates including DNA, proteins, and natural products (NPs), is accomplished by methyltransferases (MTs). Analogs of AdoMet, bearing an alternative S-alkyl group can be exploited, in the context of an array of wild-type MT-catalyzed reactions, to differentially alkylate DNA, proteins, and NPs. This technology provides a means to elucidate MT targets by the MT-mediated installation of chemoselective handles from AdoMet analogs to biologically relevant molecules and affords researchers a fresh route to diversify NP scaffolds by permitting the differential alkylation of chemical sites vulnerable to NP MTs that are unreactive to …

Discovery Of Novel Muraymycin Antibiotics And Insight Into The Biosynthetic Pathway, Zheng Cui

Theses and Dissertations--Pharmacy

New antibiotics with novel targets or mechanisms of action are needed to counter the steady emergence of bacterial pathogens that are resistant to antibiotics used in the clinic. MraY, a promising novel target for antibiotic development, initiates the lipid cycle for the biosynthesis of peptidoglycan cell wall, which is essential for the survival of most, if-not-all, bacteria. MraY is an enzyme that catalyzes the transfer and attachment of phospho-MurNAc-pentapeptide to a lipid carrier, undecaprenylphosphate. Muraymycins are recently discovered lipopeptidyl nucleoside antibiotics that exhibit remarkable antibiotic activity against Gram-positive as well as Gram-negative bacteria by inhibiting MraY. We conducted a thorough …

Chemoenzymatic Studies To Enhance The Chemical Space Of Natural Products, Jhong-Min Chen

Theses and Dissertations--Pharmacy

Natural products provide some of the most potent anticancer agents and offer a template for new drug design or improvement with the advantage of an enormous chemical space. The overall goal of this thesis research is to enhance the chemical space of two natural products in order to generate novel drugs with better in vivo bioactivities than the original natural products.

Polycarcin V (PV) is a gilvocarcin-type antitumor agent with similar structure and comparable bioactivity with the principle compound of this group, gilvocarcin V (GV). Modest modifications of the polyketide-derived tetracyclic core of GV had been accomplished, but the most …

Investigating Structure And Protein-Protein Interactions Of Key Post-Type Ii Pks Tailoring Enzymes, Theresa E. Downey

Theses and Dissertations--Pharmacy

Type II polyketide synthase (PKS) produced natural products have proven to be an excellent source of pharmacologically relevant molecules due to their rich biological activities and chemical scaffolds. Type II-PKS manufactured polyketides share similar polycyclic aromatic backbones leaving their diversity to stem from various chemical additions and alterations facilitated by post-PKS tailoring enzymes. Evidence suggests that post-PKS tailoring enzymes form complexes in order to facilitate the highly orchestrated process of biosynthesis. Thus, protein-protein interactions between these enzymes must play crucial roles in their structures and functions. Despite the importance of these interactions little has been done to study them. In …