posted on 2024-03-15, 02:29authored byKarishma Kalera, Rachel Liu, Juhyeon Lim, Rasangi Pathirage, Daniel H. Swanson, Ulysses G. Johnson, Alicyn I. Stothard, Jae Jin Lee, Anne W. Poston, Peter J. Woodruff, Donald R. Ronning, Hyungjin Eoh, Benjamin M. Swarts
Tuberculosis (TB), caused by Mycobacterium
tuberculosis (Mtb), is the leading cause of death
worldwide by infectious disease.
Treatment of Mtb infection requires a six-month course of multiple
antibiotics, an extremely challenging regimen necessitated by Mtb’s
ability to form drug-tolerant persister cells. Mtb persister formation
is dependent on the trehalose catalytic shift, a stress-responsive
metabolic remodeling mechanism in which the disaccharide trehalose
is liberated from cell surface glycolipids and repurposed as an internal
carbon source to meet energy and redox demands. Here, using a biofilm-persister
model, metabolomics, and cryo-electron microscopy (EM), we found that
azidodeoxy- and aminodeoxy-d-trehalose analogues block the
Mtb trehalose catalytic shift through inhibition of trehalose synthase
TreS (Rv0126), which catalyzes the isomerization of trehalose to maltose.
Out of a focused eight-member compound panel constructed by chemoenzymatic
synthesis, the natural product 2-trehalosamine exhibited the highest
potency and significantly potentiated first- and second-line TB drugs
in broth culture and macrophage infection assays. We also report the
first structure of TreS bound to a substrate analogue inhibitor, obtained
via cryo-EM, which revealed conformational changes likely essential
for catalysis and inhibitor binding that can potentially be exploited
for future therapeutic development. Our results demonstrate that inhibition
of the trehalose catalytic shift is a viable strategy to target Mtb
persisters and advance trehalose analogues as tools and potential
adjunctive therapeutics for investigating and targeting mycobacterial
persistence.