Characterization of two new multiforms of Trametes pubescens laccase

Research output: Contribution to journalArticle

Abstract

Electrochemical properties of two multiforms of laccase from Trametes pubescens basidiomycete (LACI and LAC2) have been studied. The standard redox potentials of the T1 sites of the enzymes were found to be 746 and 738 mV us. NHE for LACI and LAC2, respectively. Bioelectroreduction of oxygen based on direct electron transfer between each of the two forms of Trametes pubescens laccase and spectrographic graphite electrodes has been demonstrated and studied. It. is concluded that the T1 site of laccase is the first electron acceptor, both in solution (homogeneous case) and when the enzymes are adsorbed on the surface of the graphite electrode (heterogeneous case). Thus, the previously proposed mechanism of oxygen bioelectroreduction by adsorbed fungal laccase was additionally confirmed using two forms of the enzyme. Moreover, the assumed need for extracellular laccase to communicate directly and electronically with a solid matrix (lignin) in the course of lignin degradation is discussed. In summary, the possible roles of multiforms of the enzyme based on their electrochemical, biochemical, spectral, and kinetic properties have been suggested to consist in broadening of the substrate specificity of the enzyme, in turn yielding the possibility to dynamically regulate the process of lignin degradation according to the real-time survival needs of the organism.

Details

Authors
  • Sergey Shleev
  • Oxana Nikitina
  • Andreas Christenson
  • Curt Reimann
  • Alexander I. Yaropolov
  • Tautgirdas Ruzgas
  • Lo Gorton
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Analytical Chemistry

Keywords

  • lignin, T1 site, redox potential, Trametes pubescens, laccase, degradation
Original languageEnglish
Pages (from-to)35-49
JournalBioorganic Chemistry
Volume35
Issue number1
Publication statusPublished - 2007
Publication categoryResearch
Peer-reviewedYes

Bibliographic note

The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Analytical Chemistry (S/LTH) (011001004)