Modification of the peroxygenative: peroxidative activity ratio in the unspecific peroxygenase from Agrocybe aegerita by structure-guided evolution

Unspecific peroxygenase (UPO) is a heme-thiolate peroxidase capable of performing with high-selectivity C–H oxyfunctionalizations of great interest in organic synthesis through its peroxygenative activity. However, the convergence of such activity with an unwanted peroxidative activity encumbers pra...

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Detalhes bibliográficos
Autores: Maté, Diana M., Palomino, Miguel A., Molina-Espeja, Patricia, Martín-Díaz, Javier, Alcalde Galeote, Miguel
Formato: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2017
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/170426
Acesso em linha:http://hdl.handle.net/10261/170426
Access Level:acceso abierto
Palavra-chave:Structure-guided
Evolution / unspecific
Peroxygenase / peroxygenative
Activity / thermostability
Descrição
Resumo:Unspecific peroxygenase (UPO) is a heme-thiolate peroxidase capable of performing with high-selectivity C–H oxyfunctionalizations of great interest in organic synthesis through its peroxygenative activity. However, the convergence of such activity with an unwanted peroxidative activity encumbers practical applications. In this study, we have modified the peroxygenative:peroxidative activity ratio (P:p ratio) of UPO from Agrocybe aegerita by structure-guided evolution. Several flexible loops (Glu1-Pro35, Gly103-Asp131, Ser226-Gly243, Gln254-Thr276 and Ty293-Arg327) were selected on the basis on their B-factors and ΔΔG values. The full ensemble of segments (43% of UPO sequence) was subjected to focused evolution by the Mutagenic Organized Recombination Process by Homologous IN vivo Grouping (MORPHING) method in Saccharomyces cerevisiae. Five independent mutant libraries were screened in terms of P:p ratio and thermostability. We identified several variants that harbored substitutions at positions 120 and 320 with a strong enhancement in the P:p ratio albeit at the cost of stability. The most thermostable mutant of this process (S226G with an increased T50 of 2°C) was subjected to further combinatorial saturation mutagenesis on Thr120 and Thr320 yielding a collection of variants with modified P:p ratio and recovered stability. Our results seem to indicate the coexistence of several oxidation sites for peroxidative and peroxygenative activities in UPO.