Skip to main content

Table 2 Enzyme activity of examined glycoside hydrolyses on para-nitrophenyl linked glycosides (pNP-substrates)

From: The hemicellulose-degrading enzyme system of the thermophilic bacterium Clostridium stercorarium: comparative characterisation and addition of new hemicellulolytic glycoside hydrolases

Enzyme Specific enzyme activity (U/mg)
para-Nitrophenyl-
α-l-Arabinofuranoside α-d-Glucopyranoside β-d-Glucopyranoside β-d-Galactopyranoside α-l-Rhamnopyranoside β-d-Xylopyranoside β-d-Glucuronide N-acetyl-β-d-glucosaminide
Bga2B ++
Bga2E +
Bga2D + nt
Bga2C ++ nt
Uid2A (+) + + (+) +++ nt
Bxl3B ++ + +++
Bgl3Z + (+) +++ + +++
Nag3A +* +
Xyn10E (+) (+) nt
Xyn10C (+) (+) + nt
Xyn10B (+) (+) (+) ++ nt
Xyn10D (+) nt
Bxl31D + nt
Bxl39A + + nt
Axh43A ++ nt
Arf43A (+) (+) ++ nt
Arf43C ++ (+) nt
Abn43A (+) nt
Xyl43B + nt
Xyl43A (+) (+) nt
Bxl43C + ++ nt
Arf51B ++++ + nt
Ram78A (+) + +++ nt
Xyn105F (+) nt
RamB (+) nt
BglA + (+) nt
ArfD + (+) + nt
  1. Hydrolysis experiments were performed in triplicates at pH 6.5 and 60 °C in 0.1 M MOPS reaction puffer for incubation times between 10 min and up to 2 h. Enzyme activity was determined by spectrophotometric detection of released pNP. No activity was detected for 22 of 49 enzymes (not listed). Gal53A was not tested. Tested aryl-glucosides with no activity were: pNP-α-d-galactopyranoside, pNP-α-d-mannopyranoside, pNP-β-d-mannopyranoside, and pNP-α-d-xylopyranoside. Substrate was not tested (nt), incubation overnight (*), detectable but very low activity ((+)), 0.05–0.5 U/mg (+), 0.5–5.0 U/mg (++), > 5.0 U/mg (+++), > 100.0 U/mg (++++)