{"id":{"repo_id":"lethbridge","oai_identifier":"oai:opus.uleth.ca:10133/2473"},"canonical_url":"https://search.dev.ndltd.org/etd/lethbridge/oai:opus.uleth.ca:10133/2473","repository":{"repo_id":"lethbridge","name":"University of Lethbridge","base_url":"https://opus.uleth.ca/server/oai/request"},"display":{"title":"Structure and mechanism of protein tyrosine phosphatase-like phytases","abstract":"The structure and mechanism of the Protein Tyrosine Phosphatase-like Phytases (PTPLPs) from Selenomonas ruminantium (PhyAsr) and Mitsuokella multacida (PhyAmm) were investigated using a combination of enzyme kinetics, site-directed mutagenesis, and X-ray crystallography. I show that PTPLPs use a classical protein tyrosine phosphatase catalytic mechanism and adopt a core PTP fold. Several unique structural features of PTPLPs confer specificity for inositol phosphates. The effect of ionic strength and oxidation on the kinetics and structure of PTPLPs was investigated. The structural consequences of reversible and irreversible oxidation on PTPLPs and PTPs are compared and discussed. We determine the structural basis of substrate specificity in PTPLPs and propose a novel reaction mechanism for the hydrolysis of inositol polyphosphates by PTPLPs. Finally, the structure and function of a unique tandemly repeated phytase has been determined. We show that the active sites of the tandem repeat possess significantly different specificities for inositol polyphosphate.","abstract_html":"The structure and mechanism of the Protein Tyrosine Phosphatase-like Phytases (PTPLPs) from Selenomonas ruminantium (PhyAsr) and Mitsuokella multacida (PhyAmm) were investigated using a combination of enzyme kinetics, site-directed mutagenesis, and X-ray crystallography. I show that PTPLPs use a classical protein tyrosine phosphatase catalytic mechanism and adopt a core PTP fold. Several unique structural features of PTPLPs confer specificity for inositol phosphates. The effect of ionic strength and oxidation on the kinetics and structure of PTPLPs was investigated. The structural consequences of reversible and irreversible oxidation on PTPLPs and PTPs are compared and discussed. We determine the structural basis of substrate specificity in PTPLPs and propose a novel reaction mechanism for the hydrolysis of inositol polyphosphates by PTPLPs. Finally, the structure and function of a unique tandemly repeated phytase has been determined. We show that the active sites of the tandem repeat possess significantly different specificities for inositol polyphosphate.","abstract_has_math":false,"creators":["Gruninger, Robert J.","University of Lethbridge. Faculty of Arts and Science"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009","date_published":"2009","updated_at":"2026-07-27T20:02:17Z","subjects":["Phytases","Protein-tyrosine kinase","Phosphorylation","Dissertations, Academic"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["hdl:10133/2473"],"render_values":[{"text":"hdl:10133/2473","href":null,"code":true}]}]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.issued","label":"Date","values":["2009"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Phytases","Protein-tyrosine kinase","Phosphorylation","Dissertations, Academic"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["hdl:10133/2473"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.other","label":"Dc Description Other","values":["The structure and mechanism of the Protein Tyrosine Phosphatase-like Phytases (PTPLPs) from Selenomonas ruminantium (PhyAsr) and Mitsuokella multacida (PhyAmm) were investigated using a combination of enzyme kinetics, site-directed mutagenesis, and X-ray crystallography. I show that PTPLPs use a classical protein tyrosine phosphatase catalytic mechanism and adopt a core PTP fold. Several unique structural features of PTPLPs confer specificity for inositol phosphates. The effect of ionic strength and oxidation on the kinetics and structure of PTPLPs was investigated. The structural consequences of reversible and irreversible oxidation on PTPLPs and PTPs are compared and discussed. We determine the structural basis of substrate specificity in PTPLPs and propose a novel reaction mechanism for the hydrolysis of inositol polyphosphates by PTPLPs. Finally, the structure and function of a unique tandemly repeated phytase has been determined. We show that the active sites of the tandem repeat possess significantly different specificities for inositol polyphosphate."]},{"key":"dc:title","label":"Title","values":["Structure and mechanism of protein tyrosine phosphatase-like phytases"]}]}],"canonical_facts":{"dc:date.issued":["2009"],"dc:description.other":["The structure and mechanism of the Protein Tyrosine Phosphatase-like Phytases (PTPLPs) from Selenomonas ruminantium (PhyAsr) and Mitsuokella multacida (PhyAmm) were investigated using a combination of enzyme kinetics, site-directed mutagenesis, and X-ray crystallography. I show that PTPLPs use a classical protein tyrosine phosphatase catalytic mechanism and adopt a core PTP fold. Several unique structural features of PTPLPs confer specificity for inositol phosphates. The effect of ionic strength and oxidation on the kinetics and structure of PTPLPs was investigated. The structural consequences of reversible and irreversible oxidation on PTPLPs and PTPs are compared and discussed. We determine the structural basis of substrate specificity in PTPLPs and propose a novel reaction mechanism for the hydrolysis of inositol polyphosphates by PTPLPs. Finally, the structure and function of a unique tandemly repeated phytase has been determined. We show that the active sites of the tandem repeat possess significantly different specificities for inositol polyphosphate."],"dc:identifier":["hdl:10133/2473"],"dc:subject":["Phytases","Protein-tyrosine kinase","Phosphorylation","Dissertations, Academic"],"dc:title":["Structure and mechanism of protein tyrosine phosphatase-like phytases"],"dc:type":["Thesis"]},"updated_at":"2026-07-27T20:02:17Z"}