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Salt-responsive lytic polysaccharide monooxygenases from the mangrove fungus Pestalotiopsis sp. NCi6

BACKGROUND: Lytic polysaccharide monooxygenases (LPMOs) belong to the “auxiliary activities (AA)” enzyme class of the CAZy database. They are known to strongly improve the saccharification process and boost soluble sugar yields from lignocellulosic biomass, which is a key step in the efficient produ...

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Autores principales: Patel, Ilabahen, Kracher, Daniel, Ma, Su, Garajova, Sona, Haon, Mireille, Faulds, Craig B., Berrin, Jean-Guy, Ludwig, Roland, Record, Eric
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4875668/
https://www.ncbi.nlm.nih.gov/pubmed/27213015
http://dx.doi.org/10.1186/s13068-016-0520-3
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author Patel, Ilabahen
Kracher, Daniel
Ma, Su
Garajova, Sona
Haon, Mireille
Faulds, Craig B.
Berrin, Jean-Guy
Ludwig, Roland
Record, Eric
author_facet Patel, Ilabahen
Kracher, Daniel
Ma, Su
Garajova, Sona
Haon, Mireille
Faulds, Craig B.
Berrin, Jean-Guy
Ludwig, Roland
Record, Eric
author_sort Patel, Ilabahen
collection PubMed
description BACKGROUND: Lytic polysaccharide monooxygenases (LPMOs) belong to the “auxiliary activities (AA)” enzyme class of the CAZy database. They are known to strongly improve the saccharification process and boost soluble sugar yields from lignocellulosic biomass, which is a key step in the efficient production of sustainable economic biofuels. To date, most LPMOs have been characterized from terrestrial fungi, but novel fungal LPMOs isolated from more extreme environments such as an estuary mangrove ecosystem could offer enzymes with unique properties in terms of salt tolerance and higher stability under harsh condition. RESULTS: Two LPMOs secreted by the mangrove-associated fungus Pestalotiopsis sp. NCi6 (PsLPMOA and PsLPMOB) were expressed in the yeast Pichia pastoris and produced in a bioreactor with >85 mg L(−1) for PsLPMOA and >260 mg L(−1) for PsLPMOB. Structure-guided homology modeling of the PsLPMOs showed a high abundance of negative surface charges, enabling enhanced protein stability and activity in the presence of sea salt. Both PsLPMOs were activated by a cellobiose dehydrogenase (CDH) from Neurospora crassa, with an apparent optimum of interaction at pH 5.5. Investigation into their regioselective mode of action revealed that PsLPMOA released C1- and C4-oxidized cello-oligosaccharide products, while PsLPMOB released only C4-oxidized products. PsLPMOA was found to cleave polymeric cellulose in the presence of up to 6 % sea salt, which emphasizes the use of sea water in the industrial saccharification process with improved ecological footprints. CONCLUSIONS: Two new LPMOs from the mangrove fungus Pestalotiopsis sp. NCi6 were found to be fully reactive against cellulose. The combined hydrolytic activities of these salt-responsive LPMOs could therefore facilitate the saccharification process using sea water as a reaction medium for large-scale biorefineries. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13068-016-0520-3) contains supplementary material, which is available to authorized users.
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spelling pubmed-48756682016-05-22 Salt-responsive lytic polysaccharide monooxygenases from the mangrove fungus Pestalotiopsis sp. NCi6 Patel, Ilabahen Kracher, Daniel Ma, Su Garajova, Sona Haon, Mireille Faulds, Craig B. Berrin, Jean-Guy Ludwig, Roland Record, Eric Biotechnol Biofuels Research BACKGROUND: Lytic polysaccharide monooxygenases (LPMOs) belong to the “auxiliary activities (AA)” enzyme class of the CAZy database. They are known to strongly improve the saccharification process and boost soluble sugar yields from lignocellulosic biomass, which is a key step in the efficient production of sustainable economic biofuels. To date, most LPMOs have been characterized from terrestrial fungi, but novel fungal LPMOs isolated from more extreme environments such as an estuary mangrove ecosystem could offer enzymes with unique properties in terms of salt tolerance and higher stability under harsh condition. RESULTS: Two LPMOs secreted by the mangrove-associated fungus Pestalotiopsis sp. NCi6 (PsLPMOA and PsLPMOB) were expressed in the yeast Pichia pastoris and produced in a bioreactor with >85 mg L(−1) for PsLPMOA and >260 mg L(−1) for PsLPMOB. Structure-guided homology modeling of the PsLPMOs showed a high abundance of negative surface charges, enabling enhanced protein stability and activity in the presence of sea salt. Both PsLPMOs were activated by a cellobiose dehydrogenase (CDH) from Neurospora crassa, with an apparent optimum of interaction at pH 5.5. Investigation into their regioselective mode of action revealed that PsLPMOA released C1- and C4-oxidized cello-oligosaccharide products, while PsLPMOB released only C4-oxidized products. PsLPMOA was found to cleave polymeric cellulose in the presence of up to 6 % sea salt, which emphasizes the use of sea water in the industrial saccharification process with improved ecological footprints. CONCLUSIONS: Two new LPMOs from the mangrove fungus Pestalotiopsis sp. NCi6 were found to be fully reactive against cellulose. The combined hydrolytic activities of these salt-responsive LPMOs could therefore facilitate the saccharification process using sea water as a reaction medium for large-scale biorefineries. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13068-016-0520-3) contains supplementary material, which is available to authorized users. BioMed Central 2016-05-20 /pmc/articles/PMC4875668/ /pubmed/27213015 http://dx.doi.org/10.1186/s13068-016-0520-3 Text en © The Author(s). 2016 Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
spellingShingle Research
Patel, Ilabahen
Kracher, Daniel
Ma, Su
Garajova, Sona
Haon, Mireille
Faulds, Craig B.
Berrin, Jean-Guy
Ludwig, Roland
Record, Eric
Salt-responsive lytic polysaccharide monooxygenases from the mangrove fungus Pestalotiopsis sp. NCi6
title Salt-responsive lytic polysaccharide monooxygenases from the mangrove fungus Pestalotiopsis sp. NCi6
title_full Salt-responsive lytic polysaccharide monooxygenases from the mangrove fungus Pestalotiopsis sp. NCi6
title_fullStr Salt-responsive lytic polysaccharide monooxygenases from the mangrove fungus Pestalotiopsis sp. NCi6
title_full_unstemmed Salt-responsive lytic polysaccharide monooxygenases from the mangrove fungus Pestalotiopsis sp. NCi6
title_short Salt-responsive lytic polysaccharide monooxygenases from the mangrove fungus Pestalotiopsis sp. NCi6
title_sort salt-responsive lytic polysaccharide monooxygenases from the mangrove fungus pestalotiopsis sp. nci6
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4875668/
https://www.ncbi.nlm.nih.gov/pubmed/27213015
http://dx.doi.org/10.1186/s13068-016-0520-3
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