Indole Alkaloids and Phenazine Antibiotics: New Platforms For Drug Discovery Abstract: New small molecule probes and therapeutic agents are critical for the study and treatment of human disease. Our group is developing multiple chemical synthesis strategies to probe diverse biological phenomena related to human disease, including: bacterial biofilm viability, GPCR function, cancer biology and Plasmodium falciparum biology. We have developed a tryptoline-based ring distortion strategy using commercially available indole alkaloids (yohimbine and vincamine) as starting points for ring distortion, or the dramatic altering/reorganization of complex ring systems using chemoselective reactions. This approach has enabled the rapid synthesis of highly complex and diverse scaffolds for biological investigations and we have identified hit compounds in multiple disease-relevant areas pertinent to human health. Our hit compounds have gained new biological functions as their biological activities are unrelated to other scaffolds or their parent natural product, in essence, re-engineering of indole alkaloid?s chemical scaffolds and biological functions have been demonstrated. During this award, we will enhance the chemical diversity of our indole alkaloid ring distortion library by using C-H oxidation chemistry to install new synthetic handles for ring distortion and diastereoselective oxidative rearrangements to give new spirooxindole scaffolds with the ultimate goal of exploring disease-relevant chemical space with our probe molecules. In addition, our group has identified a series of halogenated phenazines (HP) that demonstrate potent biofilm-eradicating activities. These findings are significant as bacterial biofilms, or surface-attached bacterial communities, house persistent, non-replicating bacteria (persister cells) that demonstrate tolerance to all classes of antibiotics. Biofilms pose a significant threat to human health as 17 million new biofilm-associated bacterial infections occur annually that result in 550,000 deaths in the United States.
We aim to use the HP small molecules we have developed as probe molecules in RNA-seq experiments with MRSA biofilms alongside other biofilm-killing agents to investigate biofilm viability with the goal of identifying new targets and cellular pathways critical to bacterial biofilms. In addition, we aim to develop a diverse array of HP prodrugs through chemical synthesis and in vitro biological studies. Providing new insights into the basic biology critical to biofilm cell viability and developing new biofilm-eradicating prodrugs could lead to ground-breaking cures for persistent bacterial infections. Huigens (PI) Project Summary/Abstract

Public Health Relevance

New small molecule probes and therapeutic agents are critical for the study and treatment of human disease. Our group is developing multiple chemical synthesis strategies to probe diverse biological phenomena related to human disease, including: bacterial biofilm viability, GPCR function, cancer biology and Plasmodium falciparum biology. In the first strategy, our lab is developing an innovative tryptoline ring distortion approach to rapidly generate complex and diverse compounds from available indole alkaloids. In preliminary studies, we have demonstrated this approach to generate an array of compounds that have various biological activities, which will be used to explore the basic biology of cancer, GPCRs and P. falciparum. In our second chemical synthesis strategy, we are developing new bacterial selective halogenated phenazine prodrugs that can eradicate surface-attached bacterial biofilms, which lead to persistent and recurring bacterial infections. In addition, we are utilizing RNA- seq and a diverse panel of biofilm-eradicating agents as a chemical biology platform to investigate the basic biology of biofilm viability. Huigens (PI) Public Health Relevance Statement/Project Narrative

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Unknown (R35)
Project #
5R35GM128621-03
Application #
9983101
Study Section
Special Emphasis Panel (ZGM1)
Program Officer
Yang, Jiong
Project Start
2018-08-01
Project End
2023-07-31
Budget Start
2020-08-01
Budget End
2021-07-31
Support Year
3
Fiscal Year
2020
Total Cost
Indirect Cost
Name
University of Florida
Department
Pharmacology
Type
Schools of Pharmacy
DUNS #
969663814
City
Gainesville
State
FL
Country
United States
Zip Code
32611
Huigens 3rd, Robert W (2018) The Path to New Halogenated Quinolines With Enhanced Activities Against Staphylococcus epidermidis. Microbiol Insights 11:1178636118808532