Isolation and characterization of thermophilic cellulose and hemicellulose degrading bacterium, Thermoanaerobacterium sp. R63 from tropical dry deciduous forest soil

PLoS One. 2020 Jul 23;15(7):e0236518. doi: 10.1371/journal.pone.0236518. eCollection 2020.

Abstract

Thermophilic microorganisms and their enzymes have been utilized in various industrial applications. In this work, we isolated and characterized thermophilic anaerobic bacteria with the cellulose and hemicellulose degrading activities from a tropical dry deciduous forest in northern Thailand. Out of 502 isolated thermophilic anaerobic soil bacteria, 6 isolates, identified as Thermoanaerobacterium sp., displayed an ability to utilize a wide range of oligosaccharides and lignocellulosic substrates. The isolates exhibited significant cellulase and xylanase activities at high temperature (65°C). Among all isolates, Thermoanaerobacterium sp. strain R63 exhibited remarkable hydrolytic properties with the highest cellulase and xylanase activities at 1.15 U/mg and 6.17 U/mg, respectively. Extracellular extract of Thermoanaerobacterium sp. strain R63 was thermostable with an optimal temperature at 65°C and could exhibit enzymatic activities on pH range 5.0-9.0. Our findings suggest promising applications of these thermoanaerobic bacteria and their potent enzymes for industrial purposes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / metabolism
  • Biomass
  • Cellulase / metabolism
  • Cellulose / metabolism*
  • Endo-1,4-beta Xylanases / metabolism
  • Enzyme Stability
  • Hot Temperature
  • Hydrogen-Ion Concentration
  • Phylogeny
  • Polysaccharides / metabolism*
  • Soil Microbiology*
  • Substrate Specificity
  • Thermoanaerobacterium / classification
  • Thermoanaerobacterium / enzymology
  • Thermoanaerobacterium / isolation & purification
  • Thermoanaerobacterium / metabolism*

Substances

  • Bacterial Proteins
  • Polysaccharides
  • hemicellulose
  • Cellulose
  • Cellulase
  • Endo-1,4-beta Xylanases

Associated data

  • figshare/10.6084/m9.figshare.12582767.v1
  • figshare/10.6084/m9.figshare.12582779.v1
  • figshare/10.6084/m9.figshare.12582791.v1
  • figshare/10.6084/m9.figshare.12582797.v1
  • figshare/10.6084/m9.figshare.12587294.v1
  • figshare/10.6084/m9.figshare.12587306.v1

Grants and funding

This work is supported by a grant from the Center of Excellence on Biodiversity (BDC-PG1-160004) to SC. The equipment was facilitated by Central Instrument Facility (CIF) at Faculty of Science, Mahidol University.