Active site characterization of the single endo-polygalacturonase produced by Fusarium moniliforme NCIM 1276

Eur J Biochem. 2001 Feb;268(3):832-40. doi: 10.1046/j.1432-1327.2001.01959.x.

Abstract

Fusarium moniliforme NCIM 1276 isolated from a tropical mangrove ecosystem produces a single extracellular endo-polygalacturonase with an M(r) of 38 kDa and a carbohydrate content of 4%. It has an alkaline pI of 8.1. The K(m) is 0.12 mg.mL(-1), V(max) is 111.1 micromol.min(-1).mg(-1) and the kcat is 4200 min-1. It has a pH optimum of 4.8. Kinetic and fluorescence data show that tryptophan is involved in binding. An arginine residue at or near the active site may be involved in extended binding of the substrate. A carboxylate and a histidine residue are involved in catalysis. These data are discussed with reference to current literature.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / chemistry
  • Arginine / chemistry
  • Binding Sites
  • Circular Dichroism
  • Electrophoresis, Polyacrylamide Gel
  • Fusarium / enzymology*
  • Histidine / chemistry
  • Hydrogen-Ion Concentration
  • Hydrolysis
  • Kinetics
  • Pectins / chemistry
  • Polygalacturonase / chemistry*
  • Protein Binding
  • Sequence Analysis, Protein
  • Spectrometry, Fluorescence
  • Tryptophan / chemistry

Substances

  • Amino Acids
  • Histidine
  • Pectins
  • Tryptophan
  • Arginine
  • Polygalacturonase
  • polygalacturonic acid