Flavonoids are plant secondary metabolites that are integral to our lives. Grapefruits are well-known for production of unique glucosylated products and the enzymes responsible are UDP-glucose:glucosyltransferases (GTs). The objective of this research was to obtain full-length clones of putative grapefruit GTs, express them, and characterize them. Previously, gene specific primers (from conserved PSPG box) and clone specific primers (from partial 5' clones) were designed, and a compiled sequence attained using SMART RACE RT-PCR. A full-length clone was obtained using primers designed from the extreme ends of the compiled sequence. The full-length clone was inserted into expression vector (pET32a) and transformed into expression host BL21(DE3)RIL. Expressed protein was tested for GT activity using different flavonoid aglycones and UDP-14C-glucose as glucose donor. Results indicated that the expressed protein was probably not a flavonoid GT. A directionally cloned grapefruit leaf cDNA library is undergoing EST mining to identify additional GT candidates.
","abstract_html":"<p>Flavonoids are plant secondary metabolites that are integral to our lives. Grapefruits are well-known for production of unique glucosylated products and the enzymes responsible are UDP-glucose:glucosyltransferases (GTs). The objective of this research was to obtain full-length clones of putative grapefruit GTs, express them, and characterize them. Previously, gene specific primers (from conserved PSPG box) and clone specific primers (from partial 5' clones) were designed, and a compiled sequence attained using SMART RACE RT-PCR. A full-length clone was obtained using primers designed from the extreme ends of the compiled sequence. The full-length clone was inserted into expression vector (pET32a) and transformed into expression host BL21(DE3)RIL. Expressed protein was tested for GT activity using different flavonoid aglycones and UDP-<sup>14</sup>C-glucose as glucose donor. Results indicated that the expressed protein was probably not a flavonoid GT. A directionally cloned grapefruit leaf cDNA library is undergoing EST mining to identify additional GT candidates.</p>","abstract_has_math":false,"creators":["Roy Sarkar, Tapasree"],"institution":null,"degree_name":"MS (Master of Science)","degree_level":"Thesis - restricted","degree_discipline":"Biology","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2004,"date_issued":"2004-08-01T07:00:00Z","date_published":"2004-08-01T07:00:00Z","updated_at":"2026-07-24T02:19:28Z","subjects":["Naringin","Naringenin","Glucosyltransferase","EST library","Flavonoid","Biology","Life Sciences"],"languages":[],"rights":["Copyright by the authors."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://dc.etsu.edu/etd/908","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Roy Sarkar, Tapasree"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["1995-01-01T08:00:00Z"]},{"key":"dc:date.issued","label":"Date","values":["2004-08-01T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis - restricted"]},{"key":"thesis:degree_name","label":"Degree Name","values":["MS (Master of Science)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Naringin","Naringenin","Glucosyltransferase","EST library","Flavonoid","Biology","Life Sciences"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["Copyright by the authors."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://dc.etsu.edu/context/etd/article/2065/viewcontent/RoysarkarT062204f.pdf","https://dc.etsu.edu/etd/908"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Flavonoids are plant secondary metabolites that are integral to our lives. Grapefruits are well-known for production of unique glucosylated products and the enzymes responsible are UDP-glucose:glucosyltransferases (GTs). The objective of this research was to obtain full-length clones of putative grapefruit GTs, express them, and characterize them. Previously, gene specific primers (from conserved PSPG box) and clone specific primers (from partial 5' clones) were designed, and a compiled sequence attained using SMART RACE RT-PCR. A full-length clone was obtained using primers designed from the extreme ends of the compiled sequence. The full-length clone was inserted into expression vector (pET32a) and transformed into expression host BL21(DE3)RIL. Expressed protein was tested for GT activity using different flavonoid aglycones and UDP-14C-glucose as glucose donor. Results indicated that the expressed protein was probably not a flavonoid GT. A directionally cloned grapefruit leaf cDNA library is undergoing EST mining to identify additional GT candidates.
"]},{"key":"dc:title","label":"Title","values":["cDNA Cloning, Expression and Characterization of a Putative Glucosyltransferase (GT) from Grapefruit (Citrus paradisi) Leaves."]}]}],"canonical_facts":{"dc:creator":["Roy Sarkar, Tapasree"],"dc:date.available":["1995-01-01T08:00:00Z"],"dc:date.issued":["2004-08-01T07:00:00Z"],"dc:description.abstract":["Flavonoids are plant secondary metabolites that are integral to our lives. Grapefruits are well-known for production of unique glucosylated products and the enzymes responsible are UDP-glucose:glucosyltransferases (GTs). The objective of this research was to obtain full-length clones of putative grapefruit GTs, express them, and characterize them. Previously, gene specific primers (from conserved PSPG box) and clone specific primers (from partial 5' clones) were designed, and a compiled sequence attained using SMART RACE RT-PCR. A full-length clone was obtained using primers designed from the extreme ends of the compiled sequence. The full-length clone was inserted into expression vector (pET32a) and transformed into expression host BL21(DE3)RIL. Expressed protein was tested for GT activity using different flavonoid aglycones and UDP-14C-glucose as glucose donor. Results indicated that the expressed protein was probably not a flavonoid GT. A directionally cloned grapefruit leaf cDNA library is undergoing EST mining to identify additional GT candidates.
"],"dc:identifier":["https://dc.etsu.edu/context/etd/article/2065/viewcontent/RoysarkarT062204f.pdf","https://dc.etsu.edu/etd/908"],"dc:rights":["Copyright by the authors."],"dc:subject":["Naringin","Naringenin","Glucosyltransferase","EST library","Flavonoid","Biology","Life Sciences"],"dc:title":["cDNA Cloning, Expression and Characterization of a Putative Glucosyltransferase (GT) from Grapefruit (Citrus paradisi) Leaves."],"thesis:degree_discipline":["Biology"],"thesis:degree_level":["Thesis - restricted"],"thesis:degree_name":["MS (Master of Science)"]},"updated_at":"2026-07-24T02:19:28Z"}