Understanding the diversity, biochemistry, and biological role of endo-glucanase 16 enzymes in the context of plant evolution
department or school: Medicine, Faculty of
department or school: Biochemistry and Molecular Biology, Department of
data provider: DSpace
degree campus: UBCV
creator: Behar, Hila
issued: 2022-08-31T07:00:00Z
issued: 2021
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: A defining feature of plants, the plant cell wall is an essential structure that provides mechanical support, cell shape, and protection from pathogens and the environment. Cell walls are dynamic structures that are composed of a network of crystalline cellulose microfibrils, amorphous polysaccharides, and structural proteins. The synthesis, maintenance, and modification of the plant cell wall polysaccharides are carried out by carbohydrate active-enzymes (CAZymes). Xyloglucan endotransglycosylase/hydrolase (XTH) are secreted cell wall enzymes that restructure the cell wall matrix glycan, xyloglucan, thereby facilitating cell wall remodelling and growth. The plant endo-glucanase 16 (EG16) enzymes were recently identified as a unique clade that is structurally and functionally intermediate between the bacterial mixed-linkage β(1,3)/(1,4)-glucanases and the plant XTHs in glycoside hydrolase family 16 (GH16). Correspondingly, EG16 members were broadly specific towards the cell wall polysaccharides mixed-linkage β-glucan (MLG) and xyloglucan, as well as soluble cellulosic substrates. Although EG16 activity and protein structure have been demonstrated, their biological role is unknown. This thesis employs a multi-disciplinary approach to the characterization of the newly designated EG16 group. A comprehensive census of the publicly available genome and transcriptomes showed that EG16 orthologs were found in all plant clades spanning nearly 500 million years of evolution. Notably, the presence of EG16 orthologs observed in the charophyte green algae species that are the most phylogenetically distant from angiosperms, support that EG16-like genes are ancestors to extant EG16 and XTH genes. EG16 substrate specificities, primary hydrolysis site, and digest products are consistent between vastly different plant species. Elucidation of the biological role of EG16 in the moss Physcomitrella patens and a hybrid poplar species, two different distantly related land plants, show ge…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/79339
note: UNDERSTANDING THE DIVERSITY, BIOCHEMISTRY, AND BIOLOGICAL ROLE OF ENDO-GLUCANASE 16 ENZYMES IN THE CONTEXT OF PLANT EVOLUTION by Hila Behar B.Sc., Tel Aviv University, 2014 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Doctor of Philosophy in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Biochemistry and Molecular Biology) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) August 2021 © Hila Behar, 2021 ii The following individuals certify that they have read, and recommend to the Faculty of Graduate and Postdoctoral Studies for acceptance, the dissertation entitled: Understanding the diversity, biochemistry, and biological role of endo-glucanase 16 enzymes in the context of plant evolution submitted by Hila Behar in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Biochemistry and Molecular Biology Examining Committee: Prof. Harry Brumer, Chemistry, UBC Supervisor Prof. A. Lacey Samuels, Botany, UBC Supervisory Committee Member Prof. Shawn D. Mansfield, Forestry, UBC Supervisory Committee Member Prof. Ljerka Kunst, Botany, UBC University Examiner Prof. Lawrence McIntosh, Biochemistry and Molecular Biology, UBC University Examiner Additional Supervisory Committee Members: Prof. Nobuhiko Tokuriki, Biochemistry and Molecular Biology, UBC Supervisory Committee Member iii Abstract A defining feature of plants, the plant cell wall is an essential structure that provides mechanical support, cell shape, and protection from pathogens and the environment. Cell walls are dynamic structures that are composed of a network of crystalline cellulose microfibrils, amorphous polysaccharides, and structural proteins. The synthesis, maintenance, and modification of the plant cell wall polysaccharides are carried out by carbohydrate active-enzymes (CAZymes). Xyloglucan endotransglycosylase/hydrolase (XTH) are secreted cell wall enzymes that restructure the cell wall matrix glycan, xyloglucan, thereby facilitating cell w…
has type: Thesis/Dissertation
date issued: 2021-11
is shown at: 10.14288/1.0401439
language: eng
degree discipline: Biochemistry and Molecular Biology
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-ShareAlike 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-sa/4.0/
scholar level: Graduate
contributor: Brumer, Harry
type: Text
type: Other
identifier URI: http://hdl.handle.net/2429/79339