A thermostable α-arabinofuranosidase from xylanolytic Bacillus pumilus: Purification and characterisation

Giuliano Degrassi, Alessandro Vindigni, Vittorio Venturi

Research output: Contribution to journalArticlepeer-review

31 Scopus citations


Bacillus pumilus PS213 secretes an α-L-arabinofuranosidase (AF) when grown in the presence of arabinogalactan or oat meal. The enzyme has been purified to homogeneity and characterised. Its molecular mass, as determined by gel filtration, is 220 kDa, while sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) showed a single band of approximately 60 kDa. According to the result of the mass spectrometry analysis showing a molecular mass of 56 kDa, the enzyme should be a homotetramer. The isoelectric point was found to be 5.2, the enzyme activity was optimal at 55°C and pH 7.0. The enzyme retained 80% of its activity after 2 h at 65°C and lost 50% of activity at 75°C after 135 min. The Michaelis constant Km and Vmax for p-nitrophenylarabinofuranoside at 37°C were 1.7 mM and 52.9 U mg-1, respectively. N-terminal sequence analysis and internal peptide fragments showed homology with glycosyl hydrolases of family 51.

Original languageEnglish
Pages (from-to)69-79
Number of pages11
JournalJournal of Biotechnology
Issue number1
StatePublished - Feb 27 2003


  • Arabinofuranosidase
  • Bacillus pumilus
  • Enzyme purification
  • Glycosyl hydrolase family 51


Dive into the research topics of 'A thermostable α-arabinofuranosidase from xylanolytic Bacillus pumilus: Purification and characterisation'. Together they form a unique fingerprint.

Cite this