A new alkaliphilic cold-active esterase from the psychrophilic marine bacterium Rhodococcus sp.: functional and structural studies and biotechnological potential

Appl Biochem Biotechnol. 2014 Mar;172(6):3054-68. doi: 10.1007/s12010-013-0713-1. Epub 2014 Feb 1.

Abstract

The special features of cold-adapted lipolytic biocatalysts have made their use possible in several industrial applications. In fact, cold-active enzymes are known to be able to catalyze reactions at low temperatures, avoiding side reactions taking place at higher temperatures and preserving the integrity of products. A lipolytic gene was isolated from the Arctic marine bacterium Rhodococcus sp. AW25M09 and expressed in Escherichia coli as inclusion bodies. The recombinant enzyme (hereafter called RhLip) showed interesting cold-active esterase activity. The refolded purified enzyme displayed optimal activity at 30 °C and was cold-active with retention of 50% activity at 10 °C. It is worth noting that the optimal pH was 11, and the low relative activity below pH 10 revealed that RhLip was an alkaliphilic esterase. The enzyme was active toward short-chain p-nitrophenyl esters (C2-C6), displaying optimal activity with the butyrate (C4) ester. In addition, the enzyme revealed a good organic solvent and salt tolerance. These features make this an interesting enzyme for exploitation in some industrial applications.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Aquatic Organisms
  • Arctic Regions
  • Bacterial Proteins / chemistry*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Cloning, Molecular
  • Cold Temperature
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Gene Expression
  • Hydrogen-Ion Concentration
  • Inclusion Bodies / chemistry
  • Kinetics
  • Lipase / chemistry*
  • Lipase / genetics
  • Lipase / metabolism
  • Models, Molecular
  • Molecular Sequence Data
  • Protein Refolding
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Rhodococcus / chemistry*
  • Rhodococcus / enzymology
  • Salt Tolerance
  • Sequence Homology, Amino Acid
  • Substrate Specificity

Substances

  • Bacterial Proteins
  • Recombinant Proteins
  • Lipase