Molecular and Biochemical Analyses of a Novel Trifunctional Endoxylanase/Endoglucanase/Feruloyl Esterase from the Human Colonic Bacterium Bacteroides intestinalis DSM 17393

Abstract

A novel enzyme Bi76 comprising GH10, E_set_Esterase_N, and CE1 modules was identified, with the highest homology (62.9%) with a bifunctional endoxylanase/feruloyl esterase among characterized enzymes. Interestingly, Bi76 hydrolyzed glucan substrates besides xylans and feruloylated substrates, suggesting that it is the first characterized trifunctional endoxylanase/endoglucanase/feruloyl esterase. Analyses of truncation variants revealed that GH10 and E_set_Esterase_N + CE1 modules encoded endoxylanase/endoglucanase and feruloyl esterase activities, respectively. Synergism analyses indicated that endoxylanase, α-l-arabinofuranosidase, and feruloyl esterase acted cooperatively in releasing ferulic acid (FA) and xylooligosaccharides from feruloylated arabinoxylan. The interdomain synergism of Bi76 overmatched the intermolecular synergism of TM1 and TM2. Importantly, Bi76 exhibited good capacity in producing FA, releasing 5.20, 4.38, 2.12, 1.35, 0.46, and 0.19 mg/g from corn bran, corn cob, wheat bran, corn stover, rice husk, and rice bran, respectively. This study expands the trifunctional endoxylanase/endoglucanase/feruloyl esterase repertoire and demonstrates the great potential of Bi76 in agricultural residue utilization.

Impact of the herbal medicine, Ephedra sinica stapf, on gut microbiota and body weight in a diet-induced obesity model

“…Bi73 , a novel gene encoding endoxylanase and esterase, has been identified in transcriptional analysis and is highly upregulated by B. intestinalis DSM 17393 ( Zhang et al, 2014 ). Recently, molecular and biochemical analyses have reported a novel trifuctionalendoxylanase/endoglucanase/feruloyl esterase and feruloyl acid (FA)-producing B. intestinalis DSM 17393 ( Zhang et al, 2022 ). FA is a plant phenolic acid that is abundant in grains and vegetables ( Zhao and Moghadasian, 2008 ; Molinari et al, 2009 ).…”

Characterization of Feruloyl Esterase from Klebsiella oxytoca Z28 and Its Application in the Release of Ferulic Acid from De-Starching Wheat Bran

“…Zhang et al studied Bi76, a protein with FAE activity from B. intestinalis. It has good activity and stability at pH 5.5, but the FAE enzyme activity is less than 10% at pH 8.0 [25]. This result indicates that KoFAE is a relatively stable protein under alkaline conditions.…”

High efficiency production of ferulic acid using feruloyl esterase and xylanase in deep eutectic solvents

“…Second, the hydrolysis of xylanase may produce feruloylated xylooligosaccharides, which are more easily captured and degraded by feruloyl esterase. 23 Therefore, the decrease in xylanase leads to a decrease in the yield of ferulic acid. Faulds et al 24 reported that the combination of feruloyl esterase and xylanase released ferulic acid from wheat bran 24-fold than that of feruloyl esterase itself.…”