Dataset Information

Increase of Redox Potential during the Evolution of Enzymes Degrading Recalcitrant Lignin.

ABSTRACT: To investigate how ligninolytic peroxidases acquired the uniquely high redox potential they show today, their ancestors were resurrected and characterized. Unfortunately, the transient Compounds I (CI) and II (CII) from peroxide activation of the enzyme resting state (RS) are unstable. Therefore, the reduction potentials (E°') of the three redox couples (CI/RS, CI/CII and CII/RS) were estimated (for the first time in a ligninolytic peroxidase) from equilibrium concentrations analyzed by stopped-flow UV/Vis spectroscopy. Interestingly, the E°' of rate-limiting CII reduction to RS increased 70?mV from the common peroxidase ancestor to extant lignin peroxidase (LiP), and the same boost was observed for CI/RS and CI/CII, albeit with higher E°' values. A straightforward correlation was found between the E°' value and the progressive displacement of the proximal histidine H?1 chemical shift in the NMR spectra, due to the higher paramagnetic effect of the heme Fe3+ . More interestingly, the E°' and NMR data also correlated with the evolutionary time, revealing that ancestral peroxidases increased their reduction potential in the evolution to LiP thanks to molecular rearrangements in their heme pocket during the last 400 million years.

SUBMITTER: Ayuso-Fernandez I

PROVIDER: S-EPMC6582443 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Increase of Redox Potential during the Evolution of Enzymes Degrading Recalcitrant Lignin.

Ayuso-Fernández Iván I De Lacey Antonio L AL Cañada Francisco J FJ Ruiz-Dueñas Francisco J FJ Martínez Angel T AT

Chemistry (Weinheim an der Bergstrasse, Germany) 20190125 11

To investigate how ligninolytic peroxidases acquired the uniquely high redox potential they show today, their ancestors were resurrected and characterized. Unfortunately, the transient Compounds I (CI) and II (CII) from peroxide activation of the enzyme resting state (RS) are unstable. Therefore, the reduction potentials (E°') of the three redox couples (CI/RS, CI/CII and CII/RS) were estimated (for the first time in a ligninolytic peroxidase) from equilibrium concentrations analyzed by stopped- ...[more]

PMID: 30566756

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Dataset Information

Increase of Redox Potential during the Evolution of Enzymes Degrading Recalcitrant Lignin.

Publications

Increase of Redox Potential during the Evolution of Enzymes Degrading Recalcitrant Lignin.

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