MRSA and VRE are pathogenic to Caenorhabditis elegans nematodes. Based on these observations, we developed C. elegans-MRSA and C. elegans-VRE screening assays performed in 384-well plates that can be used to screen compound libraries, allowing the identification of compounds that prevent host killing that would not be detected in traditional in vitro screens for antibiotics. The ability to eliminate highly toxic compounds is particularly important for the identification of compounds with activity against bacterial membranes, as these compounds can be broadly toxic against membranes of prokaryotic and eukaryotic and toxicity is a bottle-neck for the identification of antimicrobial agents that act on the membrane. In the previous funding period, we developed an automated, high throughput C. elegans ? MRSA screening platform and screened 88,489 small synthetic molecules and obtained 257 verified hits. Among these 257 hits, we prioritized FDA approved and other well-studied compounds that we found target the bacterial membrane. Additionally, we completed a screen of 39,931 synthetic compounds using a C. elegans ? VRE infection model assay and obtained 135 verified hits, including 4 VRE inhibitory compounds that block the ability of VRE to form a persistent intestinal infection. Our current overall objective is to carry out translational studies to determine whether the compounds we have prioritized can be developed as efficacious antimicrobial compounds. We propose to determine the modes of action of compounds with activity against the membrane of MRSA (Aim 1) and prioritize anti- infective compounds that block VRE colonization of the C. elegans intestine (Aim 2).
In Aim 3, we propose to take the first steps to further develop these compounds by generating analogs, evaluating basic PK/PD characteristics, and performing efficacy studies in mouse models. In summary, we have used C. elegans-based assays to identify novel non-toxic antimicrobial compounds some of which can kill bacterial cells that are in a non-planktonic form of growth. We anticipate that the proposed studies will allow the discovery of potentially novel targets for antimicrobial drug discovery and identify potential lead compounds with activity against multi-drug resistant Gram-positive pathogens.

Public Health Relevance

There is an urgent need for the development of new antibiotic agents in order to combat the increasing number of severe infections and the development of resistance. The main objective of this proposal is to study the efficacy of a compound that is active even against bacteria that are in a metabolically inactive state and thus are resistant to conventional antibiotics. Because of its novel activity, this compound has the potential to play a pivotal role in the management of patients with chronic bacterial infections.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Program Projects (P01)
Project #
5P01AI083214-13
Application #
9996467
Study Section
Special Emphasis Panel (ZAI1)
Project Start
2009-09-01
Project End
2021-08-31
Budget Start
2020-09-01
Budget End
2021-08-31
Support Year
13
Fiscal Year
2020
Total Cost
Indirect Cost
Name
Massachusetts Eye and Ear Infirmary
Department
Type
DUNS #
073825945
City
Boston
State
MA
Country
United States
Zip Code
02114
Bispo, Paulo J M; Davoudi, Samaneh; Sahm, Matthew L et al. (2018) Rapid Detection and Identification of Uveitis Pathogens by Qualitative Multiplex Real-Time PCR. Invest Ophthalmol Vis Sci 59:582-589
Lieberman, Mia T; Van Tyne, Daria; Dzink-Fox, JoAnn et al. (2018) Long-Term Colonization Dynamics of Enterococcus faecalis in Implanted Devices in Research Macaques. Appl Environ Microbiol 84:
Kim, Wooseong; Hendricks, Gabriel L; Tori, Katerina et al. (2018) Strategies against methicillin-resistant Staphylococcus aureus persisters. Future Med Chem 10:779-794
Tharmalingam, Nagendran; Port, Jenna; Castillo, Dawilmer et al. (2018) Repurposing the anthelmintic drug niclosamide to combat Helicobacter pylori. Sci Rep 8:3701
Liu, Qingzhong; Zheng, Zhaojun; Kim, Wooseong et al. (2018) Influence of subinhibitory concentrations of NH125 on biofilm formation & virulence factors of Staphylococcus aureus. Future Med Chem 10:1319-1331
Jagadeesan, Sakthimala; Hakkim, Abdul (2018) RNAi Screening: Automated High-Throughput Liquid RNAi Screening in Caenorhabditis elegans. Curr Protoc Mol Biol 124:e65
Wood, B McKay; Santa Maria Jr, John P; Matano, Leigh M et al. (2018) A partial reconstitution implicates DltD in catalyzing lipoteichoic acid d-alanylation. J Biol Chem 293:17985-17996
Tharmalingam, Nagendran; Rajmuthiah, Rajmohan; Kim, Wooseong et al. (2018) Antibacterial Properties of Four Novel Hit Compounds from a Methicillin-Resistant Staphylococcus aureus-Caenorhabditis elegans High-Throughput Screen. Microb Drug Resist 24:666-674
Truong-Bolduc, Q C; Wang, Y; Hooper, D C (2018) Tet38 Efflux Pump Contributes to Fosfomycin Resistance in Staphylococcus aureus. Antimicrob Agents Chemother 62:
Lebreton, Fran├žois; Valentino, Michael D; Schaufler, Katharina et al. (2018) Transferable vancomycin resistance in clade B commensal-type Enterococcus faecium. J Antimicrob Chemother 73:1479-1486

Showing the most recent 10 out of 145 publications