Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2024 May 16;206(6):261.
doi: 10.1007/s00203-024-03982-w.

Heteroxylan hydrolysis by a recombinant cellulase-free GH10 xylanase from the alkaliphilic bacterium Halalkalibacterium halodurans C-125

Jihene Maati  1 , Duarte Miguel Prazeres  2   3 , Marcin Grąz  4 , Adrian Wiater  5 , Anna Jarosz-Wilkołazka  4 , Issam Smaali  6
Affiliations

Heteroxylan hydrolysis by a recombinant cellulase-free GH10 xylanase from the alkaliphilic bacterium Halalkalibacterium halodurans C-125

Jihene Maati et al. Arch Microbiol. .

Abstract

The search for affordable enzymes with exceptional characteristics is fundamental to overcoming industrial and environmental constraints. In this study, a recombinant GH10 xylanase (Xyn10-HB) from the extremely alkaliphilic bacterium Halalkalibacterium halodurans C-125 cultivated at pH 10 was cloned and expressed in E. coli BL21(DE3). Removal of the signal peptide improved the expression, and an overall activity of 8 U/mL was obtained in the cell-free supernatant. The molecular weight of purified Xyn10-HB was estimated to be 42.6 kDa by SDS-PAGE. The enzyme was active across a wide pH range (5-10) with optimal activity recorded at pH 8.5 and 60 °C. It also presented good stability with a half-life of 3 h under these conditions. Substrate specificity studies showed that Xyn10-HB is a cellulase-free enzyme that conventionally hydrolyse birchwood and oat spelts xylans (Apparent Km of 0.46 mg/mL and 0.54 mg/mL, respectively). HPLC analysis showed that both xylans hydrolysis produced xylooligosaccharides (XOS) with a degree of polymerization (DP) ranging from 2 to 9. The conversion yield was 77% after 24 h with xylobiose and xylotriose as the main end-reaction products. When assayed on alkali-extracted wheat straw heteroxylan, the Xyn10-HB produced active XOS with antioxidant activity determined by the DPPH radical scavenging method (IC50 of 0.54 mg/mL after 4 h). Owing to its various characteristics, Xyn10-HB xylanase is a promising candidate for multiple biotechnological applications.

Keywords: Halalkalibacterium halodurans C-125; Active xylooligosaccharides; Alkaliphilicity; Cellulase-free; GH10 xylanase.

PubMed Disclaimer

References

    1. Aachary AA, Prapulla SG (2009) Value addition to corncob: production and characterization of xylooligosaccharides from alkali pretreated lignin-saccharide complex using Aspergillus oryzae MTCC 5154. Bioresour Technol 100:991–995. https://doi.org/10.1016/j.biortech.2008.06.050 - DOI - PubMed
    1. Bai W, Xue Y, Zhou C, Ma Y (2012) Cloning, expression and characterization of a novel salt-tolerant xylanase from Bacillus sp. SN5. Biotechnol Lett 34:2093–2099. https://doi.org/10.1007/s10529-012-1011-7 - DOI - PubMed
    1. Bhardwaj A, Bharadwaj A, Leelavathi S et al (2008) The critical role of partially exposed N-terminal valine residue in stabilizing GH10 xylanase from Bacillus sp. NG-27 under poly-extreme conditions. PLoS ONE 3:e3063. https://doi.org/10.1371/journal.pone.0003063 - DOI - PubMed
    1. Bhardwaj N, Kumar B, Verma P (2019) A detailed overview of xylanases: an emerging biomolecule for current and future prospective. Bioresour Bioprocess 6:40. https://doi.org/10.1186/s40643-019-0276-2 - DOI
    1. Biely P, Vršanská M, Tenkanen M, Kluepfel D (1997) Endo-β-1,4-xylanase families: differences in catalytic properties. J Biotechnol 57:151–166. https://doi.org/10.1016/S0168-1656(97)00096-5 - DOI - PubMed

MeSH terms

LinkOut - more resources