Show simple item record

dc.contributor.authorGawin, Agnieszka Maria
dc.contributor.authorTietze, Lisa
dc.contributor.authorAarstad, Olav Andreas
dc.contributor.authorAachmann, Finn Lillelund
dc.contributor.authorBrautaset, Trygve
dc.contributor.authorErtesvåg, Helga
dc.identifier.citationScientific Reports. 2020, 10en_US
dc.description.abstractBacterial alginate initially consists of 1-4-linked beta-D-mannuronic acid residues (M) which can be later epimerized to alpha-L-guluronic acid (G). The family of AlgE mannuronan C-5-epimerases from Azotobacter vinelandii has been extensively studied, and three genes putatively encoding AlgE-type epimerases have recently been identified in the genome of Azotobacter chroococcum. The three A. chroococcum genes, here designated AcalgE1, AcalgE2 and AcalgE3, were recombinantly expressed in Escherichia coli and the gene products were partially purified. The catalytic activities of the enzymes were stimulated by the addition of calcium ions in vitro. AcAlgE1 displayed epimerase activity and was able to introduce long G-blocks in the alginate substrate, preferentially by attacking M residues next to pre-existing G residues. AcAlgE2 and AcAlgE3 were found to display lyase activities with a substrate preference toward M-alginate. AcAlgE2 solely accepted M residues in the positions - 1 and + 2 relative to the cleavage site, while AcAlgE3 could accept either M or G residues in these two positions. Both AcAlgE2 and AcAlgE3 were bifunctional and could also catalyze epimerization of M to G. Together, we demonstrate that A. chroococcum encodes three different AlgE-like alginate-modifying enzymes and the biotechnological and biological impact of these findings are discussed.en_US
dc.publisherNature Researchen_US
dc.rightsNavngivelse 4.0 Internasjonal*
dc.titleFunctional characterization of three Azotobacter chroococcum alginate-modifying enzymes related to the Azotobacter vinelandii AlgE mannuronan C-5-epimerase familyen_US
dc.typePeer revieweden_US
dc.typeJournal articleen_US
dc.source.journalScientific Reportsen_US
dc.relation.projectNorges forskningsråd: 220005en_US
dc.relation.projectNorges forskningsråd: 257147en_US
dc.relation.projectNorges forskningsråd: 250875en_US
dc.relation.projectNorges forskningsråd: 226244en_US
dc.relation.projectNorges forskningsråd: 294946en_US
dc.description.localcodeOpen Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as 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 images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit

Files in this item


This item appears in the following Collection(s)

Show simple item record

Navngivelse 4.0 Internasjonal
Except where otherwise noted, this item's license is described as Navngivelse 4.0 Internasjonal