Structural analysis of rice Os4BGlu18 monolignol β-glucosidase.
Monolignol glucosides are storage forms of monolignols, which are polymerized to lignin to strengthen plant cell walls. The conversion of monolignol glucosides to monolignols is catalyzed by monolignol β-glucosidases. Rice Os4BGlu18 β-glucosidase catalyzes hydrolysis of the monolignol glucosides, co...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2021-01-01
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| Series: | PLoS ONE |
| Online Access: | https://doi.org/10.1371/journal.pone.0241325 |
| _version_ | 1828069941676343296 |
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| author | Supaporn Baiya Salila Pengthaisong Sunan Kitjaruwankul James R Ketudat Cairns |
| author_facet | Supaporn Baiya Salila Pengthaisong Sunan Kitjaruwankul James R Ketudat Cairns |
| author_sort | Supaporn Baiya |
| collection | DOAJ |
| description | Monolignol glucosides are storage forms of monolignols, which are polymerized to lignin to strengthen plant cell walls. The conversion of monolignol glucosides to monolignols is catalyzed by monolignol β-glucosidases. Rice Os4BGlu18 β-glucosidase catalyzes hydrolysis of the monolignol glucosides, coniferin, syringin, and p-coumaryl alcohol glucoside more efficiently than other natural substrates. To understand more clearly the basis for substrate specificity of a monolignol β-glucosidase, the structure of Os4BGlu18 was determined by X-ray crystallography. Crystals of Os4BGlu18 and its complex with δ-gluconolactone diffracted to 1.7 and 2.1 Å resolution, respectively. Two protein molecules were found in the asymmetric unit of the P212121 space group of their isomorphous crystals. The Os4BGlu18 structure exhibited the typical (β/α)8 TIM barrel of glycoside hydrolase family 1 (GH1), but the four variable loops and two disulfide bonds appeared significantly different from other known structures of GH1 β-glucosidases. Molecular docking studies of the Os4BGlu18 structure with monolignol substrate ligands placed the glycone in a similar position to the δ-gluconolactone in the complex structure and revealed the interactions between protein and ligands. Molecular docking, multiple sequence alignment, and homology modeling identified amino acid residues at the aglycone-binding site involved in substrate specificity for monolignol β-glucosides. Thus, the structural basis of substrate recognition and hydrolysis by monolignol β-glucosidases was elucidated. |
| first_indexed | 2024-04-11T00:28:19Z |
| format | Article |
| id | doaj.art-5b0895559526483480e26ab1afcae030 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-04-11T00:28:19Z |
| publishDate | 2021-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-5b0895559526483480e26ab1afcae0302023-01-08T05:31:56ZengPublic Library of Science (PLoS)PLoS ONE1932-62032021-01-01161e024132510.1371/journal.pone.0241325Structural analysis of rice Os4BGlu18 monolignol β-glucosidase.Supaporn BaiyaSalila PengthaisongSunan KitjaruwankulJames R Ketudat CairnsMonolignol glucosides are storage forms of monolignols, which are polymerized to lignin to strengthen plant cell walls. The conversion of monolignol glucosides to monolignols is catalyzed by monolignol β-glucosidases. Rice Os4BGlu18 β-glucosidase catalyzes hydrolysis of the monolignol glucosides, coniferin, syringin, and p-coumaryl alcohol glucoside more efficiently than other natural substrates. To understand more clearly the basis for substrate specificity of a monolignol β-glucosidase, the structure of Os4BGlu18 was determined by X-ray crystallography. Crystals of Os4BGlu18 and its complex with δ-gluconolactone diffracted to 1.7 and 2.1 Å resolution, respectively. Two protein molecules were found in the asymmetric unit of the P212121 space group of their isomorphous crystals. The Os4BGlu18 structure exhibited the typical (β/α)8 TIM barrel of glycoside hydrolase family 1 (GH1), but the four variable loops and two disulfide bonds appeared significantly different from other known structures of GH1 β-glucosidases. Molecular docking studies of the Os4BGlu18 structure with monolignol substrate ligands placed the glycone in a similar position to the δ-gluconolactone in the complex structure and revealed the interactions between protein and ligands. Molecular docking, multiple sequence alignment, and homology modeling identified amino acid residues at the aglycone-binding site involved in substrate specificity for monolignol β-glucosides. Thus, the structural basis of substrate recognition and hydrolysis by monolignol β-glucosidases was elucidated.https://doi.org/10.1371/journal.pone.0241325 |
| spellingShingle | Supaporn Baiya Salila Pengthaisong Sunan Kitjaruwankul James R Ketudat Cairns Structural analysis of rice Os4BGlu18 monolignol β-glucosidase. PLoS ONE |
| title | Structural analysis of rice Os4BGlu18 monolignol β-glucosidase. |
| title_full | Structural analysis of rice Os4BGlu18 monolignol β-glucosidase. |
| title_fullStr | Structural analysis of rice Os4BGlu18 monolignol β-glucosidase. |
| title_full_unstemmed | Structural analysis of rice Os4BGlu18 monolignol β-glucosidase. |
| title_short | Structural analysis of rice Os4BGlu18 monolignol β-glucosidase. |
| title_sort | structural analysis of rice os4bglu18 monolignol β glucosidase |
| url | https://doi.org/10.1371/journal.pone.0241325 |
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