Isolation and characterization of novel pI 4.8 MnP isoenzyme from white-rot fungus Irpex lacteus

J. Sklenar, M. L. Niku-Paavola, S. Santos, P. Man, K. Kruus, C. Novotny*

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

22 Citations (Scopus)


Growth of Irpex lacteus on polyurethane solid support led to secretion of various manganese-dependent peroxidase (MnP) isoenzymes with pI in the range of 3.8-6.7. The highest MnP activity was obtained at 8.9mmoll-1 Mn2+ when predominantly a pI 4.8 isoenzyme was produced. Optimization of anion exchange chromatography (Mono Q) allowed the separation of MnP isoenzymes and collection of extensive sequence information by tandem LC-MS. The pI 4.8 isoenzyme was purified 109-fold (6% activity yield) by ion exchange chromatography, its specific activity of Mn2+ oxidation was 2800nkatmg-1, molecular mass 37kDa and pH optimum 5. The other properties were: respective half-lives (pH 4.5) of 575, 325 and 7min at 40, 50 and 60°C, Km values 46.7; 9.5; 21.4μmoll-1 and kcat values 69.0; 64.2; 15.7s-1 for Mn2+, H2O2 and DMP with Mn2+, respectively. The pI 4.8 isoenzyme was shown to be a true MnP affecting secondary substrates via the oxidation of Mn2+. Its biochemical properties and production by I. lacteus make the enzyme a candidate for biotechnological applications.

Original languageEnglish
Pages (from-to)550-556
Number of pages7
JournalEnzyme and Microbial Technology
Issue number7
Publication statusPublished - 1 Jun 2010
MoE publication typeA1 Journal article-refereed


  • Enzyme isolation
  • Irpex lacteus
  • MnP isoenzymes
  • Selective secretion
  • Solid-support growth
  • White-rot fungus


Dive into the research topics of 'Isolation and characterization of novel pI 4.8 MnP isoenzyme from white-rot fungus Irpex lacteus'. Together they form a unique fingerprint.

Cite this