Commensal Bacterium Rothia aeria Degrades and Detoxifies Gluten via a Highly Effective Subtilisin Enzyme

• Published in: Nutrients Vol. 12; no. 12; p. 3724
• Main Authors: Wei, Guoxian, Darwish, Ghassan, Oppenheim, Frank G, Schuppan, Detlef, Helmerhorst, Eva J
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 02.12.2020; MDPI
• Subjects: Animals; Autoimmune diseases; Bacillus; Bacteria; Bacteria - metabolism; Biodegradation; Celiac disease; Celiac Disease - metabolism; degradation; Digestive tract; Enzymatic activity; Enzyme activity; Enzyme-linked immunosorbent assay; Enzymes; epitope; Epitopes; Ethanol; Gel electrophoresis; Gliadin; Gluten; Glutens - metabolism; Hydrogen-Ion Concentration; Immunoblotting; Immunogenicity; Intestine; Mice; Mice, Inbred BALB C; Micrococcaceae - metabolism; Mouth - metabolism; Neutralization; Oral cavity; Peptides; Probiotics; Proteins; Rothia; Rye; Small intestine; Software; Spectrometry; Stomach; Subtilisin; Subtilisin - metabolism; Symbiosis; Wheat; United States > US; detoxify; gluten; neutralize; Rothia; Bacillus; celiac disease; commensal; degradation; cure; epitope; subtilisin
• ISSN: 2072-6643; 2072-6643
• DOI: 10.3390/nu12123724

Celiac disease is characterized by a chronic immune-mediated inflammation of the small intestine, triggered by gluten contained in wheat, barley, and rye. , a gram-positive natural colonizer of the oral cavity and the upper digestive tract is able to degrade and detoxify gluten in vitro. The objective of this study was to assess gluten-degrading activity of live and dead bacteria in vitro, and to isolate the gluten-degrading enzyme. After an overnight fast, Balb/c mouse were fed a 1 g pellet of standard chow containing 50% wheat (and 4% gliadin) with or without 1.6 × 10 live bacteria. After 2 h, in vivo gluten degradation was assessed in gastric contents by SDS-PAGE and immunoblotting, and immunogenic epitope neutralization was assessed with the R5 gliadin ELISA assay. enzyme isolation and identification was accomplished by separating proteins in the bacterial cell homogenate by C18 chromatography followed by gliadin zymography and mass spectrometric analysis of excised bands. In mice fed with , gliadins and immunogenic epitopes were reduced by 20% and 33%, respectively, as compared to gluten digested in control mice. Killing of bacteria in ethanol did not abolish enzyme activity associated with the bacteria. The gluten degrading enzyme was identified as BAV86562.1, here identified as a member of the subtilisin family. This study shows the potential of to be used as a first probiotic for gluten digestion in vivo, either as live or dead bacteria, or, alternatively, for using the purified enzyme, to benefit the gluten-intolerant patient population.