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Phylogeny and structure of the cinnamyl alcohol dehydrogenase gene family in Brachypodium distachyon

Cinnamyl alcohol dehydrogenase (CAD) catalyses the final step of the monolignol biosynthesis, the conversion of cinnamyl aldehydes to alcohols, using NADPH as a cofactor. Seven members of the CAD gene family were identified in the genome of Brachypodium distachyon and five of these were isolated and...

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Autores principales: Bukh, Christian, Nord-Larsen, Pia Haugaard, Rasmussen, Søren K.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Oxford University Press 2012
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3481213/
https://www.ncbi.nlm.nih.gov/pubmed/23028019
http://dx.doi.org/10.1093/jxb/ers275
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author Bukh, Christian
Nord-Larsen, Pia Haugaard
Rasmussen, Søren K.
author_facet Bukh, Christian
Nord-Larsen, Pia Haugaard
Rasmussen, Søren K.
author_sort Bukh, Christian
collection PubMed
description Cinnamyl alcohol dehydrogenase (CAD) catalyses the final step of the monolignol biosynthesis, the conversion of cinnamyl aldehydes to alcohols, using NADPH as a cofactor. Seven members of the CAD gene family were identified in the genome of Brachypodium distachyon and five of these were isolated and cloned from genomic DNA. Semi-quantitative reverse-transcription PCR revealed differential expression of the cloned genes, with BdCAD5 being expressed in all tissues and highest in root and stem while BdCAD3 was only expressed in stem and spikes. A phylogenetic analysis of CAD-like proteins placed BdCAD5 on the same branch as bona fide CAD proteins from maize (ZmCAD2), rice (OsCAD2), sorghum (SbCAD2) and Arabidopsis (AtCAD4, 5). The predicted three-dimensional structures of both BdCAD3 and BdCAD5 resemble that of AtCAD5. However, the amino-acid residues in the substrate-binding domains of BdCAD3 and BdCAD5 are distributed symmetrically and BdCAD3 is similar to that of poplar sinapyl alcohol dehydrogenase (PotSAD). BdCAD3 and BdCAD5 expressed and purified from Escherichia coli both showed a temperature optimum of about 50 °C and molar weight of 49kDa. The optimal pH for the reduction of coniferyl aldehyde were pH 5.2 and 6.2 and the pH for the oxidation of coniferyl alcohol were pH 8 and 9.5, for BdCAD3 and BdCAD5 respectively. Kinetic parameters for conversion of coniferyl aldehyde and coniferyl alcohol showed that BdCAD5 was clearly the most efficient enzyme of the two. These data suggest that BdCAD5 is the main CAD enzyme for lignin biosynthesis and that BdCAD3 has a different role in Brachypodium. All CAD enzymes are cytosolic except for BdCAD4, which has a putative chloroplast signal peptide adding to the diversity of CAD functions.
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spelling pubmed-34812132012-10-26 Phylogeny and structure of the cinnamyl alcohol dehydrogenase gene family in Brachypodium distachyon Bukh, Christian Nord-Larsen, Pia Haugaard Rasmussen, Søren K. J Exp Bot Research Paper Cinnamyl alcohol dehydrogenase (CAD) catalyses the final step of the monolignol biosynthesis, the conversion of cinnamyl aldehydes to alcohols, using NADPH as a cofactor. Seven members of the CAD gene family were identified in the genome of Brachypodium distachyon and five of these were isolated and cloned from genomic DNA. Semi-quantitative reverse-transcription PCR revealed differential expression of the cloned genes, with BdCAD5 being expressed in all tissues and highest in root and stem while BdCAD3 was only expressed in stem and spikes. A phylogenetic analysis of CAD-like proteins placed BdCAD5 on the same branch as bona fide CAD proteins from maize (ZmCAD2), rice (OsCAD2), sorghum (SbCAD2) and Arabidopsis (AtCAD4, 5). The predicted three-dimensional structures of both BdCAD3 and BdCAD5 resemble that of AtCAD5. However, the amino-acid residues in the substrate-binding domains of BdCAD3 and BdCAD5 are distributed symmetrically and BdCAD3 is similar to that of poplar sinapyl alcohol dehydrogenase (PotSAD). BdCAD3 and BdCAD5 expressed and purified from Escherichia coli both showed a temperature optimum of about 50 °C and molar weight of 49kDa. The optimal pH for the reduction of coniferyl aldehyde were pH 5.2 and 6.2 and the pH for the oxidation of coniferyl alcohol were pH 8 and 9.5, for BdCAD3 and BdCAD5 respectively. Kinetic parameters for conversion of coniferyl aldehyde and coniferyl alcohol showed that BdCAD5 was clearly the most efficient enzyme of the two. These data suggest that BdCAD5 is the main CAD enzyme for lignin biosynthesis and that BdCAD3 has a different role in Brachypodium. All CAD enzymes are cytosolic except for BdCAD4, which has a putative chloroplast signal peptide adding to the diversity of CAD functions. Oxford University Press 2012-10 2012-10-01 /pmc/articles/PMC3481213/ /pubmed/23028019 http://dx.doi.org/10.1093/jxb/ers275 Text en © 2012 The Authors. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.0/uk/) which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Research Paper
Bukh, Christian
Nord-Larsen, Pia Haugaard
Rasmussen, Søren K.
Phylogeny and structure of the cinnamyl alcohol dehydrogenase gene family in Brachypodium distachyon
title Phylogeny and structure of the cinnamyl alcohol dehydrogenase gene family in Brachypodium distachyon
title_full Phylogeny and structure of the cinnamyl alcohol dehydrogenase gene family in Brachypodium distachyon
title_fullStr Phylogeny and structure of the cinnamyl alcohol dehydrogenase gene family in Brachypodium distachyon
title_full_unstemmed Phylogeny and structure of the cinnamyl alcohol dehydrogenase gene family in Brachypodium distachyon
title_short Phylogeny and structure of the cinnamyl alcohol dehydrogenase gene family in Brachypodium distachyon
title_sort phylogeny and structure of the cinnamyl alcohol dehydrogenase gene family in brachypodium distachyon
topic Research Paper
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3481213/
https://www.ncbi.nlm.nih.gov/pubmed/23028019
http://dx.doi.org/10.1093/jxb/ers275
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