Journal: Redox Biology
Article Title: Formation of a reducing microenvironment and regulation of protein supersulfidation by gut microbial supersulfides
doi: 10.1016/j.redox.2026.104123
Figure Lengend Snippet: Supersulfides shape the extracellular redox environment and oxidative stress resistance (A) Each bacterial strain was incubated with cystine. Cell pellets and culture supernatants were collected to obtain intracellular and extracellular fractions, respectively. Heatmap colors represent fold changes of the absorbance values in the cystine-supplemented group relative to the vehicle control. (B) Levels of supersulfides in intracellular and extracellular fractions after incubation with cystine were quantified using LC-ESI-MS/MS. The extracellular-to-intracellular ratio of supersulfides was then calculated and expressed as a relative value compared with the vehicle control. (C, D) Bacterial culture supernatants with or without cystine were treated with NEM, and thiol levels and reducing capacity were analyzed using DTNB (C) and WST-8 (D). (E) Bacterial culture supernatants with or without cystine were treated with H 2 O 2 , and residual H 2 O 2 was quantified. Data was normalized to the optical density at 600 nm (OD 600 ). (F) Intracellular oxidative stress levels in each bacterial strain after H 2 O 2 exposure were analyzed by flow cytometry. For the cystine-supplemented group, bacteria were pre-cultured in the presence of cystine prior to H 2 O 2 treatment. Data are expressed as the means ± SEM. Statistical significance was assessed using unpaired Student's t -test in (B) and (E) or one-way ANOVA followed by Holm–Šidák multiple comparisons test in (C, D) and (F). ∗ p < 0.05; ∗∗ p < 0.01; ∗∗∗ p < 0.001.
Article Snippet: Next, 190 μL of bacterial lysate were mixed with 10 μL of WST-8 reagent (Tokyo Chemical Industry Co., Ltd., Tokyo, Japan) and incubated for 2 h at room temperature.
Techniques: Incubation, Control, Tandem Mass Spectroscopy, Flow Cytometry, Bacteria, Cell Culture