Cloning, expression and characterization of a metagenome derived thermoactive/thermostable pectinase

Mol Biol Rep. 2012 Aug;39(8):8353-61. doi: 10.1007/s11033-012-1685-x. Epub 2012 Jun 19.

Abstract

The gene encoding a thermostable pectinase was isolated from a soil metagenome sample. The gene sequence corresponded to an open reading frame of 1,311 bp encoding a translation product of 47.9 kDa. It showed maximum (93 %) identity to a Bacillus licheniformis glycoside hydrolase. Deduced amino acid analysis showed an absence of highly conserved cysteine residues in the N-terminal region at positions 24 and 42, and in the C-terminal region at positions 389, 394, 413 and 424. pQpecJKR01 (pQE30 expression vector containing the pectinase gene) was expressed in Escherichia coli strain M15 as a recombinant fusion protein containing an N-terminal 6× His tag. Biochemical properties of this pectinase were novel. The enzyme had temperature and pH optima of 70 °C and 7.0, respectively, but was active over a broad temperature and pH range. The enzyme was stable at 60 °C with a half-life of 5 h and the enzyme activity was inhibited by 0.1 % diethyl pyrocarbonate and 5 mM dicyclohexyl carbodiimide. The enzyme could be of great use in industrial processes due to its activity over a broad pH range and at high temperature.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacillus / enzymology*
  • Bacillus / genetics*
  • Cloning, Molecular
  • Enzyme Activation
  • Enzyme Stability
  • Gene Expression
  • Hot Temperature
  • Metagenome*
  • Molecular Sequence Data
  • Polygalacturonase / genetics*
  • Polygalacturonase / metabolism*
  • Sequence Homology, Amino Acid
  • Substrate Specificity

Substances

  • Polygalacturonase

Associated data

  • GENBANK/FJ538208