Antibiotic resistant bacterial infections pose a serious threat to human health. Resistance is increasing while research into new antibiotics and possible new targets is lagging. Both Gram-positive and Gram-negative bacteria are surrounded by a cross-linked carbohydrate polymer, peptidoglycan (PG). This polymer is essential for bacterial survival because it stabilizes the cell membrane against high internal osmotic pressures. Peptidoglycan biosynthesis is a major target for antibiotics because interfering with this process leads to cell lysis. Indeed, the beta-lactams and glycopeptide antibiotics inhibit PG biosynthesis. Many PG biosynthetic enzymes are already targeted by clinically used antibiotics; however, one class of especially promising targets, the peptidoglycan glycosyltransferases (PGTs), remains unexploited. This research program is focused on discovering inhibitors of PGTs. These enzymes are attractive targets because their functions are essential, their structures are highly conserved in all bacteria, they have no mammalian homologs and they are located on the outer surface of the plasma membrane, which makes them more accessible to inhibitors than intracellular enzymes. The research described here constitutes an integrated, comprehensive program to discover and develop PGT inhibitors using library screening, synthetic organic chemistry, biochemical and cellular assays, structural studies, and bacterial genetics. The proposed work may lead to new compounds to treat antibiotic-resistant infections.

Public Health Relevance

Antibiotic resistant bacterial infections pose a major threat to human health and new antibiotics are desperately needed. Bacterial peptidoglycan is a well-established target for clinically useful antibiotics, but for one promising family of enzymes in th pathway, the peptidoglycan glycosyltransferases, there are still no drugs. This research constitutes a comprehensive, interdisciplinary program to discover and develop antibiotics that inhibit these enzymes.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM066174-16
Application #
9452066
Study Section
Synthetic and Biological Chemistry A Study Section (SBCA)
Program Officer
Fabian, Miles
Project Start
2002-07-01
Project End
2019-03-31
Budget Start
2018-04-01
Budget End
2019-03-31
Support Year
16
Fiscal Year
2018
Total Cost
Indirect Cost
Name
Harvard University
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
082359691
City
Cambridge
State
MA
Country
United States
Zip Code
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