A cysteine protease isolated from the latex of Ficus microcarpa: purification and biochemical characterization

Appl Biochem Biotechnol. 2015 Feb;175(3):1732-44. doi: 10.1007/s12010-014-1376-2. Epub 2014 Nov 26.

Abstract

A plant protease named microcarpain was purified from the latex of Ficus microcarpa by acetonic (20-40 % saturation) precipitation, Sephadex G-75 filtration, and Mono Q-Sefinose FF chromatography. The protease was purified with a yield of 9.25 % and a purification factor of 8. The molecular weight of the microcarpain was estimated to be 20 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The purified enzyme showed maximum activity at pH 8.0 and at a temperature of 70 °C. Proteolytic activity was strongly inhibited by dithio-bis-nitrobenzoic acid (DTNB), Hg(2+), and Cu(2+). The N-terminal amino acid sequence of the purified microcarpain "VPETVDWRSKGAV" showed high homology with a protease from Arabidopsis thaliana. Inhibition studies and N-terminal sequence classified the enzyme as a member of the cysteine peptidases family.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Chromatography, Gel
  • Cysteine / pharmacology
  • Cysteine Proteases / chemistry
  • Cysteine Proteases / isolation & purification*
  • Cysteine Proteases / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Enzyme Stability / drug effects
  • Ficus / enzymology*
  • Hydrogen-Ion Concentration
  • Hydrolysis / drug effects
  • Ions
  • Latex / metabolism*
  • Metals / pharmacology
  • Molecular Sequence Data
  • Molecular Weight
  • Protease Inhibitors / pharmacology
  • Proteolysis / drug effects
  • Substrate Specificity / drug effects
  • Temperature

Substances

  • Ions
  • Latex
  • Metals
  • Protease Inhibitors
  • Cysteine Proteases
  • Cysteine