The Ability of Basic and Glycosylated Proline-Rich Proteins to Protect Oral Enzymes from Polyphenol Inhibition.

Tannins and flavan-3-ols can exhibit astringency and potential antinutritional effects by binding, aggregating, and precipitating proteins, including digestive and oral enzymes. During oral food processing, these polyphenolic compounds may inhibit enzymes, such as β-glucosidase and glutathione transferase (GSTP1), which help generate taste-active molecules or transform food components for elimination. Saliva contains proline-rich proteins (PRPs) with high affinity for tannins and flavan-3-ols, potentially protecting oral enzymes from inhibition.

Characterization of a Human Respiratory Mucosa Model to Study Odorant Metabolism.

Nasal xenobiotic metabolizing enzymes (XMEs) are important for the sense of smell because they influence odorant availability and quality. Since the major part of the human nasal cavity is lined by a respiratory mucosa, we hypothesized that this tissue contributed to nasal odorant metabolism through XME activity. Thus, we built human respiratory tissue models and characterized the XME profiles using single-cell RNA sequencing.

Glutathione Transferase Omega 1 Localization in Oral Tissues and Interactions with Food Phytochemicals.

Glutathione transferases are xenobiotic-metabolizing enzymes with both glutathione-conjugation and ligandin roles. GSTs are present in chemosensory tissues and fluids of the nasal/oral cavities where they protect tissues from exogenous compounds, including food molecules. In the present study, we explored the presence of the omega-class glutathione transferase (GSTO1) in the rat oral cavity.

Structure-activity analysis suggests an olfactory function for the unique antennal delta glutathione transferase of Apis mellifera.

Glutathione transferases (GST) are detoxification enzymes that conjugate glutathione to a wide array of molecules. In the honey bee Apis mellifera, AmGSTD1 is the sole member of the delta class of GSTs, with expression in antennae. Here, we structurally and biochemically characterized AmGSTD1 to elucidate its function.