The emergence of hydrogen sulfide (H S) as an important signalling molecule in redox biology with therapeutic potential has triggered interest in generating this molecule within cells. One strategy that has been proposed is to use carbonyl sulfide (COS) as a surrogate for hydrogen sulfide. Small molecules that generate COS have been shown to produce hydrogen sulfide in the presence of carbonic anhydrase, a widely prevalent enzyme.
View Article and Find Full Text PDFReactive oxygen species (ROS) are transient, highly reactive intermediates or byproducts produced during oxygen metabolism. However, when innate mechanisms are unable to cope with sequestration of surplus ROS, oxidative stress results, in which excess ROS damage biomolecules. Oxidized phosphatidylserine (PS), a proapoptotic 'eat me' signal, is produced in response to elevated ROS, yet little is known regarding its chemical composition and metabolism.
View Article and Find Full Text PDFFluoroquinolones (FQs) are among the front-line antibiotics used to treat severe infections caused by Gram-negative bacteria. However, recently, due to toxicity concerns, their use has been severely restricted. Hence, efforts to direct delivery of this antibiotic specifically to bacteria/site of infection are underway.
View Article and Find Full Text PDFA series of cell-permeable esterase-sensitive sulfonates that undergo self-immolation to produce sulfur dioxide (SO), a gaseous pollutant with new and emerging biological roles, is reported. These compounds should facilitate the study SO biology and will lay the platform for newer stimuli-responsive donors of this gas.
View Article and Find Full Text PDFThera/NO - a small molecule that is activated by hydrogen peroxide to generate nitric oxide (NO) and a fluorescence signal is reported. Using cancer and primary cells, we show that Thera/NO preferentially releases NO in cancer cells, which can trigger DNA damage and cell death in them. The coupled fluorescence signal facilitated tracking the NO release in living cells without collateral consumption of NO.
View Article and Find Full Text PDFNitric oxide (NO) plays significant signalling roles in cells; the controlled generation of NO is of therapeutic relevance. Although a number of methods for the delivery and detection of NO are available, these events are typically mutually exclusive. Furthermore, the efficiency of delivery of NO can be compromised by detection technologies that consume NO.
View Article and Find Full Text PDFHydrogen sulfide (HS) is a mediator of a number of cellular processes, and modulating cellular levels of this gas has emerged as an important therapeutic area. Localized generation of HS is thus very useful but highly challenging. Here, we report pivaloyloxymethyl-based carbonothioates and carbamothioates that are activated by the enzyme, esterase, to generate carbonyl sulfide (COS), which is hydrolyzed to HS.
View Article and Find Full Text PDFHere, we report the design, synthesis, and evaluation of arylboronate ester based diazeniumdiolates (BORO/NO), a class of nitric oxide (NO) donors activated by hydrogen peroxide (H2O2), a reactive oxygen species (ROS), to generate NO. We provide evidence for the NO donors' ability to permeate bacteria to produce NO when exposed to H2O2 supporting possible applications for BORO/NO to study molecular mechanisms of NO generation in response to elevated ROS.
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