In:
Scientific Reports, Springer Science and Business Media LLC, Vol. 11, No. 1 ( 2021-12-09)
Abstract:
Cruciferous vegetables are rich sources of glucosinolates (GSLs). GSLs are degraded into isothiocyanates, which are potent anticarcinogens, by human gut bacteria. However, the mechanisms and enzymes involved in gut bacteria-mediated GSL metabolism are currently unclear. This study aimed to elucidate the enzymes involved in GSL metabolism in lactic acid bacteria, a type of gut bacteria. Companilactobacillus farciminis KB1089 was selected as a lactic acid bacteria strain model that metabolizes sinigrin, which is a GSL, into allylisothiocyanate. The sinigrin-metabolizing activity of this strain is induced under glucose-absent and sinigrin-present conditions. A quantitative comparative proteomic analysis was conducted and a total of 20 proteins that were specifically expressed in the induced cells were identified. Three candidate proteins, β-glucoside-specific IIB, IIC, IIA phosphotransferase system (PTS) components ( Cf PttS), 6-phospho-β-glucosidase ( Cf PbgS) and a hypothetical protein ( Cf NukS), were suspected to be involved in sinigrin-metabolism and were thus investigated further. We hypothesize a pathway for sinigrin degradation, wherein sinigrin is taken up and phosphorylated by Cf PttS, and subsequently, the phosphorylated entity is degraded by Cf PbgS. As expression of both pttS and pbgS genes clearly gave Escherichia coli host strain sinigrin converting activity, these genes were suggested to be responsible for sinigrin degradation. Furthermore, heterologous expression analysis using Lactococcus lactis suggested that Cf PttS was important for sinigrin degradation and Cf PbgS degraded phosphorylated sinigrin.
Type of Medium:
Online Resource
ISSN:
2045-2322
DOI:
10.1038/s41598-021-03064-7
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2021
detail.hit.zdb_id:
2615211-3
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