Isolation, characterization, and interaction of lignin-degrading bacteria from rumen of buffalo (Bubalus bubalis)

J Basic Microbiol. 2021 Aug;61(8):757-768. doi: 10.1002/jobm.202100068. Epub 2021 Jun 8.

Abstract

The purpose of this study was to isolate lignin-degrading bacteria from buffalo rumen and to explore their interactions further. Using lignin as the carbon source, three bacteria, B-04 (Ochrobactrum pseudintermedium), B-11 (Klebsiella pneumoniae), and B-45 (Bacillus sonorensis), which have shown lignin degradation potential, were successfully isolated and identified from the rumen fluid of buffalo by colony morphology, 16S ribosomal RNA gene sequencing, and biochemical and physiological analyses. The degradation rates of lignin were determined, and the maximum values were 4.86%, 11.1%, and 7.68% for B-04, B-11, and B-45, respectively. The maximum laccase activities were 0.65, 0.93, and 1.15 U/ml, while the maximum lignin peroxidase activities were 5.72, 8.29, and 18.69 U/ml, respectively. Pairwise interaction studies showed inhibitory interaction between B-04 and B-45, inhibitory interaction between B-04 and B-11, and symbiotic interaction between B-11 and B-45. This is the first report on the lignin degradation ability of bacteria isolated from the buffalo's rumen, which provides a new understanding for revealing the mechanism of roughage tolerance of buffalo.

Keywords: bacterial interaction; buffalo rumen; lignin-degrading bacteria; lignin-degrading enzyme.

MeSH terms

  • Animals
  • Bacillus / isolation & purification
  • Bacillus / metabolism
  • Bacteria / classification
  • Bacteria / genetics
  • Bacteria / isolation & purification*
  • Bacteria / metabolism*
  • Buffaloes / microbiology*
  • Klebsiella pneumoniae / isolation & purification
  • Klebsiella pneumoniae / metabolism
  • Lignin / metabolism*
  • Microbial Interactions
  • Ochrobactrum / isolation & purification
  • Ochrobactrum / metabolism
  • Phylogeny
  • RNA, Ribosomal, 16S / genetics
  • Rumen / microbiology*
  • Sequence Alignment

Substances

  • RNA, Ribosomal, 16S
  • Lignin

Supplementary concepts

  • Bacillus sonorensis
  • Ochrobactrum pseudintermedium