Mapping the Long-Range Electron Transfer Route in Ligninolytic Peroxidases
Journal article, 2017

Combining a computational analysis with site-directed mutagenesis, we have studied the long-range electron transfer pathway in versatile and lignin peroxidases, two enzymes of biotechnological interest that play a key role for fungal degradation of the bulky lignin molecule in plant biomass. The in silico study established two possible electron transfer routes starting at the surface tryptophan residue previously identified as responsible for oxidation of the bulky lignin polymer. Moreover, in both enzymes, a second buried tryptophan residue appears as a top electron transfer carrier, indicating the prevalence of one pathway. Site-directed mutagenesis of versatile peroxidase (from Pleurotus eryngii) allowed us to corroborate the computational analysis and the role played by the buried tryptophan (Trp244) and a neighbor phenylalanine residue (Phe198), together with the surface tryptophan, in the electron transfer. These three aromatic residues are highly conserved in all the sequences analyzed (up to a total of 169). The importance of the surface (Trp171) and buried (Trp251) tryptophan residues in lignin peroxidase has been also confirmed by directed mutagenesis of the Phanerochaete chrysosporium enzyme. Overall, the combined procedure identifies analogous electron transfer pathways in the long-range oxidation mechanism for both ligninolytic peroxidases, constituting a good example of how computational analysis avoids making extensive trial-error mutagenic experiments.

Author

S. Acebes

Barcelona Supercomputing Center (BSC)

F. J. Ruiz-Duenas

CSIC - Centro de Investigaciones Biologicas (CIB)

M. Toubes

CSIC - Centro de Investigaciones Biologicas (CIB)

Veronica Saez Jimenez

CSIC - Centro de Investigaciones Biologicas (CIB)

M. Perez-Boada

CSIC - Centro de Investigaciones Biologicas (CIB)

M. F. Lucas

Catalan Institution for Research and Advanced Studies

Barcelona Supercomputing Center (BSC)

A. T. Martinez

CSIC - Centro de Investigaciones Biologicas (CIB)

V. Guallar

Catalan Institution for Research and Advanced Studies

Barcelona Supercomputing Center (BSC)

Journal of Physical Chemistry B

1520-6106 (ISSN) 1520-5207 (eISSN)

Vol. 121 16 3946-3954

Subject Categories

Structural Biology

DOI

10.1021/acs.jpcb.7b00835

PubMed

28375014

More information

Latest update

1/21/2020