# Enzymatic Production of Prebiotic Xylooligosaccharides Using a Bacillus pumilus GH30_8 Glucuronoxylanase: Structural Basis of Glucuronoxylan Recognition and Hydrolysis

## TL;DR

A new enzyme from Bacillus pumilus efficiently produces prebiotic xylooligosaccharides from plant biomass, showing potential for use in nutrition and biotechnology.

## Contribution

A novel GH30_8 glucuronoxylanase from Bacillus pumilus is characterized for prebiotic XOS production with structural and functional insights.

## Key findings

- BpXyn30_8A produces both linear and branched xylooligosaccharides containing MeGlcA.
- The enzyme achieves higher xylan conversion yields from corn cob and Eucalyptus sawdust than RcXyn30A.
- Bifidobacterium adolescentis metabolizes neutral XOS to acetate and lactate but poorly utilizes acidic XOS.

## Abstract

Transformation of agro-industrial products into value-added
products,
such as prebiotic oligosaccharides, is a key element of the emerging
bioeconomy. Here, we characterized a new GH30_8 glucuronoxylanase
from Bacillus pumilus (BpXyn30_8A) for its potential in producing xylooligosaccharides (XOS). BpXyn30_8A showed tolerance to ethanol and NaCl and released
both linear and branched XOS containing MeGlcA at the penultimate
nonreducing end residue. Its X-ray structure, determined at 2.16 Å
resolution, revealed high similarity to other glucuronoxylanases.
Furthermore, BpXyn30_8A achieved higher xylan conversion
yields from corn cob and Eucalyptus sawdust than Ruminococcus champanellensis
RcXyn30A. Finally, fermentation assays showed that Bifidobacterium adolescentis metabolized neutral
XOS to acetate and lactate, whereas acidic XOS were poorly utilized.
These results highlight the potential of BpXyn30_8A
as a valuable enzyme for the green transformation of plant biomass
into prebiotic oligosaccharides with promising applications in human
and animal nutrition, health, and biotechnology.