Xylanase modulates the microbiota of ileal mucosa and digesta of pigs fed corn-based arabinoxylans likely through both a stimbiotic and prebiotic mechanism

PLoS One. 2021 Jan 27;16(1):e0246144. doi: 10.1371/journal.pone.0246144. eCollection 2021.

Abstract

The experimental objective was to characterize the impact of insoluble corn-based fiber, xylanase, and an arabinoxylan-oligosaccharide on ileal digesta and mucosa microbiome of pigs. Three replicates of 20 gilts were blocked by initial body weight, individually-housed, and assigned to 1 of 4 dietary treatments: a low-fiber control (LF), a 30% corn bran high-fiber control (HF), HF+100 mg/kg xylanase (HF+XY), and HF+50 mg/kg arabinoxylan oligosaccharide (HF+AX). Gilts were fed their respective treatments for 46 days. On day 46, pigs were euthanized and ileal digesta and mucosa were collected. The V4 region of the 16S rRNA was amplified and sequenced, generating a total of 2,413,572 and 1,739,013 high-quality sequences from the digesta and mucosa, respectively. Sequences were classified into 1,538 mucosa and 2,495 digesta operational taxonomic units (OTU). Hidden-state predictions of 25 enzymes were made using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States 2 (PICRUST2). Compared to LF, HF increased Erysipelotrichaceae_UCG-002, and Turicibacter in the digesta, Lachnospiraceae_unclassified in the mucosa, and decreased Actinobacillus in both (Q<0.05). Relative to HF, HF+XY increased 19 and 14 of the 100 most abundant OTUs characterized from digesta and mucosa, respectively (Q<0.05). Notably, HF+XY increased the OTU_23_Faecalibacterium by nearly 6 log2-fold change, compared to HF. Relative to HF, HF+XY increased genera Bifidobacterium, and Lactobacillus, and decreased Streptococcus and Turicibacter in digesta (Q<0.05), and increased Bifidobacterium and decreased Escherichia-Shigella in the mucosa (Q<0.05). Compared to HF, HF+AX increased 5 and 6 of the 100 most abundant OTUs characterized from digesta and mucosa, respectively, (Q<0.05), but HF+AX did not modulate similar taxa as HF+XY. The PICRUST2 predictions revealed HF+XY increased gene-predictions for enzymes associated with arabinoxylan degradation and xylose metabolism in the digesta, and increased enzymes related to short-chain fatty acid production in the mucosa. Collectively, these data suggest xylanase elicits a stimbiotic and prebiotic mechanism.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animal Feed*
  • Animals
  • Bacteria* / classification
  • Bacteria* / enzymology
  • Bacteria* / genetics
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Endo-1,4-beta Xylanases / genetics
  • Endo-1,4-beta Xylanases / metabolism*
  • Gastrointestinal Microbiome / drug effects*
  • Ileum / microbiology*
  • Intestinal Mucosa / microbiology*
  • Swine / microbiology*
  • Xylans / pharmacology*

Substances

  • Bacterial Proteins
  • Xylans
  • arabinoxylan
  • Endo-1,4-beta Xylanases

Grants and funding

Amy Petry (AP) is a recipient of a United States Department of Agriculture National Institute of Food and Agriculture (USDA‐AFRI; https://nifa.usda.gov) National Needs Fellowship for Ph.D. Studies (Grant # 2016‐38420‐25496). USDA‐AFRI provided support in the form of salaries for AP only, but the funder did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. This study was supported by AB Vista, and they provided the xylanase and AXOS used in this trial. MR Bedford is an employee of AB Vista. As one of the authors, MB had influence over the study design. However, MB had a smaller role in the decision to publish or preparation of the manuscript, and there was no point at which conclusions or interpretations put forward, that were suggested by MB, without full agreement of the other authors. AB Vista was involved in the conceptualization of the project and study design. The specific roles of all authors are articulated in the ‘author contributions’ section.