Targeting Persistence through Inhibition of the Trehalose Catalytic Shift.

Tuberculosis (TB), caused by (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.

The role of chemoenzymatic synthesis in advancing trehalose analogues as tools for combatting bacterial pathogens.

Trehalose, a disaccharide of glucose, is increasingly recognized as an important contributor to virulence in major bacterial pathogens, such as Mycobacterium tuberculosis, Clostridioides difficile, and Burkholderia pseudomallei. Accordingly, bacterial trehalose metabolic pathways that are not present in humans have gained traction as targets for antibiotic and diagnostic development. Toward this goal, trehalose can be modified through a combination of rational design and synthesis to produce functionalized trehalose analogues, which can be deployed to probe or inhibit bacterial trehalose metabolism.

Degradation-resistant trehalose analogues block utilization of trehalose by hypervirulent Clostridioides difficile.

Trehalose is used as an additive in thousands of foods, cosmetics, and pharmaceutical products, and it is being investigated as a therapeutic for multiple human diseases. However, its ability to be used as a carbon source by microbes is a concern, as highlighted by the recent finding that trehalose can be metabolized by and potentially enhance the virulence of epidemic Clostridioides difficile. Here, we show that trehalose analogues designed to resist enzymatic degradation are incapable of being used as carbon sources by C.

Chemoenzymatic radiosynthesis of 2-deoxy-2-[F]fluoro-d-trehalose ([F]-2-FDTre): A PET radioprobe for in vivo tracing of trehalose metabolism.

Trehalose analogues bearing fluorescent and click chemistry tags have been developed as probes of bacterial trehalose metabolism, but these tools have limitations with respect to in vivo imaging applications. Here, we report the radiosynthesis of the F-modified trehalose analogue 2-deoxy-2-[F]fluoro-d-trehalose ([F]-2-FDTre), which in principle can be used in conjunction with positron emission tomography (PET) imaging to allow in vivo imaging of trehalose metabolism in various contexts. A chemoenzymatic method employing the thermophilic TreT enzyme from Thermoproteus tenax was used to rapidly (15-20 min), efficiently (70% radiochemical yield; ≥ 95% radiochemical purity), and reproducibly convert the commercially available radiotracer 2-deoxy-2-[F]fluoro-d-glucose ([F]-2-FDG) into the target radioprobe [F]-2-FDTre in a single step; both manual and automated syntheses were performed with similar results.

Chemoenzymatic Synthesis of Trehalosamine, an Aminoglycoside Antibiotic and Precursor to Mycobacterial Imaging Probes.

Trehalosamine (2-amino-2-deoxy-α,α-d-trehalose) is an aminoglycoside with antimicrobial activity against Mycobacterium tuberculosis, and it is also a versatile synthetic intermediate used to access imaging probes for mycobacteria. To overcome inefficient chemical synthesis approaches, we report a two-step chemoenzymatic synthesis of trehalosamine that features trehalose synthase (TreT)-catalyzed glycosylation as the key transformation. Soluble and recyclable immobilized forms of TreT were successfully employed.

Tailoring Trehalose for Biomedical and Biotechnological Applications.

Trehalose is a non-reducing sugar whose ability to stabilize biomolecules has brought about its widespread use in biological preservation applications. Trehalose is also an essential metabolite in a number of pathogens, most significantly the global pathogen , though it is absent in humans and other mammals. Recently, there has been a surge of interest in modifying the structure of trehalose to generate analogues that have applications in biomedical research and biotechnology.

The trehalose-specific transporter LpqY-SugABC is required for antimicrobial and anti-biofilm activity of trehalose analogues in Mycobacterium smegmatis.

Mycobacteria, including the bacterial pathogen that causes human tuberculosis, possess distinctive pathways for synthesizing and utilizing the non-mammalian disaccharide trehalose. Trehalose metabolism is essential for mycobacterial viability and has been linked to in vitro biofilm formation, which may bear relevance to in vivo drug tolerance. Previous research has shown that some trehalose analogues bearing modifications at the 6-position inhibit growth of various mycobacterial species.

Rapid One-step Enzymatic Synthesis and All-aqueous Purification of Trehalose Analogues.

Chemically modified versions of trehalose, or trehalose analogues, have applications in biology, biotechnology, and pharmaceutical science, among other fields. For instance, trehalose analogues bearing detectable tags have been used to detect Mycobacterium tuberculosis and may have applications as tuberculosis diagnostic imaging agents. Hydrolytically stable versions of trehalose are also being pursued due to their potential for use as non-caloric sweeteners and bioprotective agents.

Deoxyfluoro-d-trehalose (FDTre) analogues as potential PET probes for imaging mycobacterial infection.

Mycobacterium tuberculosis, the etiological agent of human tuberculosis, requires the non-mammalian disaccharide trehalose for growth and virulence. Recently, detectable trehalose analogues have gained attention as probes for studying trehalose metabolism and as potential diagnostic imaging agents for mycobacterial infections. Of particular interest are deoxy-[(18)F]fluoro-d-trehalose ((18)F-FDTre) analogues, which have been suggested as possible positron emission tomography (PET) probes for in vivo imaging of M.

Chemoenzymatic synthesis of trehalose analogues: rapid access to chemical probes for investigating mycobacteria.

Trehalose analogues are emerging as valuable tools for investigating Mycobacterium tuberculosis, but progress in this area is slow due to the difficulty in synthesizing these compounds. Here, we report a chemoenzymatic synthesis of trehalose analogues that employs the heat-stable enzyme trehalose synthase (TreT) from the hyperthermophile Thermoproteus tenax. By using TreT, various trehalose analogues were prepared quickly (1 h) in high yield (up to >99 % by HPLC) in a single step from readily available glucose analogues.

Chromate reduction is expedited by bacteria engineered to produce the compatible solute trehalose.

The toxicity and solubility of chromium(VI) can be decreased by certain microbes that reduce chromium(VI) to chromium(III). However, these bacteria do not escape unscathed from this process. Chromium(VI) reduction damages the essential macromolecules of living systems.

Trehalose is required for growth of Mycobacterium smegmatis.

Mycobacteria contain high levels of the disaccharide trehalose in free form as well as within various immunologically relevant glycolipids such as cord factor and sulfolipid-1. By contrast, most bacteria use trehalose solely as a general osmoprotectant or thermoprotectant. Mycobacterium tuberculosis and Mycobacterium smegmatis possess three pathways for the synthesis of trehalose.