Continuously emerging new and hard-to-treat microbes, and the growing incidence of multi-drug resistant infections pose formidable challenges to human health. Innovative approaches are urgently needed to speed up the discovery of new anti-infectives.
Our aim i s to achieve a paradigm shift in antimicrobial drug discovery by finding next generation anti-infectives that prevent disease by blocking pathogen adaptation to host physiology. To this end we propose using whole live animals for high throughput screening of small molecules. We have developed infection models in the nematode Caenorhabditis elegans that can be used to identify drugs that cure otherwise lethal infections. High throughput screening of nematodes in 384-well plates is followed by secondary screening in a more highly evolved model host, the fruit fly Drosophila melanogaster, increasing the likelihood of isolating drugs that will work in humans. Our approach is applicable to many different classes of microorganisms, including bacteria, viruses, fungi and parasites. It has several advantages over traditional drug discovery: (i) In addition to identifying conventional antibiotics, it will uncover entirely new classes of anti-infectives that only exhibit in vivo activity. Examples are """"""""virulence blockers"""""""" and """"""""immune escape blockers"""""""". (ii) Our approach is unbiased and requires no prior knowledge of potential drug targets or pathways. (iii) It bypasses the current bottleneck of toxicity/efficacy testing by automatically eliminating toxic compounds (because they would kill the nematodes), yielding quality hits with in vivo activity. (iv) It will identify compounds that prevent or mitigate microbial resistance development, or can be combined with antibiotic therapy, thereby increasing antibiotic efficacy. We predict that our approach can identify compounds that inhibit diverse aspects of virulence: (i) adhesion and colonization, (ii) epithelial barrier disruption, (iii) deep tissue invasion, (iv) biofilm formation, (v) avoidance of immune recognition, and (vi) modulation of immune signaling. Some of the molecular mechanisms underlying these processes are conserved across bacterial species. To establish proof-of-principle, we seek funding for discovering new anti-infectives against Pseudomonas aeruginosa, one of several gram-negative bacteria that have recently emerged in a multi-drug resistant form for which efficient antibiotics are either limited or not available. We plan to screen a large number of chemical compounds (250,000) to maximize the discovery of new classes of anti-infectives. Promising compounds will undergo characterization, efficacy testing in other gram-negative bacteria (Klebsiella, Acinetobacter, Enterobacter) and testing in mouse models of infection. For highly promising candidates we will attempt molecular target identification.

Public Health Relevance

Microbes that cause disease are becoming resistant to antibiotics faster than we can find new ones, making many common infections untreatable and life threatening. The goal of our project is to find a way to identify a new generation of antibiotics. Rather than simply preventing bacteria from growing, these new sophisticated drugs will prevent disease by interfering with a microbe's ability to interact with the human body.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI085581-04
Application #
8312372
Study Section
Special Emphasis Panel (ZRG1-BCMB-A (51))
Program Officer
Xu, Zuoyu
Project Start
2009-09-28
Project End
2014-08-31
Budget Start
2012-09-01
Budget End
2013-08-31
Support Year
4
Fiscal Year
2012
Total Cost
$1,035,268
Indirect Cost
$450,371
Name
Massachusetts General Hospital
Department
Type
DUNS #
073130411
City
Boston
State
MA
Country
United States
Zip Code
02199
Haller, Samantha; Franchet, Adrien; Hakkim, Abdul et al. (2018) Quorum-sensing regulator RhlR but not its autoinducer RhlI enables Pseudomonas to evade opsonization. EMBO Rep 19:
Cezairliyan, Brent; Ausubel, Frederick M (2017) Investment in secreted enzymes during nutrient-limited growth is utility dependent. Proc Natl Acad Sci U S A 114:E7796-E7802
Kirienko, Daniel R; Revtovich, Alexey V; Kirienko, Natalia V (2016) A High-Content, Phenotypic Screen Identifies Fluorouridine as an Inhibitor of Pyoverdine Biosynthesis and Pseudomonas aeruginosa Virulence. mSphere 1:
Cheesman, Hilary K; Feinbaum, Rhonda L; Thekkiniath, Jose et al. (2016) Aberrant Activation of p38 MAP Kinase-Dependent Innate Immune Responses Is Toxic to Caenorhabditis elegans. G3 (Bethesda) 6:541-9
McEwan, Deborah L; Feinbaum, Rhonda L; Stroustrup, Nicholas et al. (2016) Tribbles ortholog NIPI-3 and bZIP transcription factor CEBP-1 regulate a Caenorhabditis elegans intestinal immune surveillance pathway. BMC Biol 14:105
Jayamani, Elamparithi; Rajamuthiah, Rajmohan; Larkins-Ford, Jonah et al. (2015) Insect-derived cecropins display activity against Acinetobacter baumannii in a whole-animal high-throughput Caenorhabditis elegans model. Antimicrob Agents Chemother 59:1728-37
Rajamuthiah, Rajmohan; Jayamani, Elamparithi; Majed, Hiwa et al. (2015) Antibacterial properties of 3-(phenylsulfonyl)-2-pyrazinecarbonitrile. Bioorg Med Chem Lett 25:5203-7
Kirienko, Natalia V; Ausubel, Frederick M; Ruvkun, Gary (2015) Mitophagy confers resistance to siderophore-mediated killing by Pseudomonas aeruginosa. Proc Natl Acad Sci U S A 112:1821-6
Rajamuthiah, Rajmohan; Jayamani, Elamparithi; Conery, Annie L et al. (2015) A Defensin from the Model Beetle Tribolium castaneum Acts Synergistically with Telavancin and Daptomycin against Multidrug Resistant Staphylococcus aureus. PLoS One 10:e0128576
Conery, Annie L; Larkins-Ford, Jonah; Ausubel, Frederick M et al. (2014) High-throughput screening for novel anti-infectives using a C. elegans pathogenesis model. Curr Protoc Chem Biol 6:25-37

Showing the most recent 10 out of 24 publications