Selenium Decipher: Trapping of Native Selenomethionine-Containing Peptides in Selenium-Enriched Milk and Unveiling the Deterioration after Ultrahigh-Temperature Treatment

Abstract

Selenopeptide identification relies on databases to interpret the selenopeptide spectra. A common database search strategy is to set selenium as a variable modification instead of sulfur on peptides. However, this approach generally detects only a fraction of selenopeptides. An alternative approach, termed Selenium Decipher, is proposed in the present study. It involves identifying collision-induced dissociation-cleavable selenomethionine-containing peptides by iteratively matching the masses of seleno-amino acids in selenopeptide spectra. This approach uses variable-data-independent acquisition (vDIA) for peptide detection, providing a flexible and customizable window for secondary mass spectral fragmentation. The attention mechanism was used to capture global information on peptides and determine selenomethionine-containing peptide backbones. The core structure of selenium on selenomethionine-containing peptides generates a series of fragment ions, namely, C

Selenium-Mediated (−)-Epigallocatechin-3-Gallate Dynamics via Flavanone-3-Hydroxylase Regulation of Flavonoid Biosynthesis in Fu Tea (Camellia sinensis (L.) O. Kuntze)

“…We identified a novel selenopeptide PRSeMW in selenium-enriched Fu tea samples, and its molecular weight and amino acid sequence ( m / z 636.22571, Pro-Arg-SeMet-Trp) were determined by UHPLC-Q-Orbitrap MS/MS. Fragmentation of the parent peptide ion produced selenium in the core structure of the selenomethionine-containing peptide, yielding a series of fragmentation ions (Figure ), as in the validation of many peptides containing selenomethionine-substituted peptides . The PeptideRanker predicted a predicted score of PRSeMW (0.977), with potential bioactivity; and there was no toxicity as predicted by ToxinPred toxicity.…”

“…Catechins and flavonols share a metabolic pathway for flavonoid synthesis, with naringenin being catalyzed by flavonoid 3-hydroxylase (F3H) to produce dihydrokaempferol, and flavonol synthase (FLS), flavonoid 3′5′-hydroxylase (F3′5’H), and flavonoid 3′-hydroxylase (F3′H) differentiating the biosynthesis of dihydrokaempferol into cannabinol, dihydrquercetin, and dihydromyricetin to produce the myricetin 3-glycosides, quercetin, and catechin compounds (Figure ). , …”

“…Tea (Camellia sinensis) trees in selenium-enriched areas and under selenium fertilizer conditions have a high capacity for selenium enrichment, which may cause the occurrence of oxidative stress and protein misfolding in tea plants. , Selenium enriched in tea tree is incorporated into the catalytic sites of proteins in the form of selenomethionine and selenocysteine (Figure B). Selenocysteine tRNA Sec (Sec-tRNA Sec ) was incorporated into selenoprotein polypeptides in the simultaneous presence of the cis-element of the Sec incorporation sequence (SECIS), SECIS-binding protein 2 (SBP2), and a dedicated eukaryotic elongation factor (eEFSec). , …”

Formation and hazard of ethyl carbamate and construction of genetically engineered Saccharomyces cerevisiae strains in Huangjiu (Chinese grain wine)

“…Temperature can affect the content of EC precursors during the fermentation process. The citrulline showed an increase in concentration with the rise of temperature, whereas the concentration of arginine decreased during the aging process (Wu & Jia, 2024;Jia et al, 2022a). EC forms rapidly after frying.…”