Biochemical and Structural Studies of Pseudouridine 55 Synthase
Phannachet, Kulwadee
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/84812
Description
Title
Biochemical and Structural Studies of Pseudouridine 55 Synthase
Author(s)
Phannachet, Kulwadee
Issue Date
2005
Doctoral Committee Chair(s)
Huang, Raven H.
Department of Study
Biochemistry
Discipline
Biochemistry
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Chemistry, Biochemistry
Language
eng
Abstract
Sequence alignment of the families of PsiS identifies the conserved aspartic acid discussed previously as the strictly conserved amino acid. Structural alignment identifies the conserved tyrosine, which is part of hydrophobic core in the active site. The role of the conserved tyrosine is less obvious in addition to apparent structural role. Enzymatic activity assay reveals that mutating T. maritima Tyr67 to any other amino acids abolishes the enzymatic activity. Structure of T. maritima Y67F in complex with the 5FU-RNA reveals, however, that the same 5FhPsi product formed by wild-type Psi55S is also found in the active site. Furthermore, HPLC analysis indicates that 5FhPsi is also formed when 5FU RNA was incubated with either E. coli Y76F or Y76L but not with Y76A. The combined information from structural, biochemical and mutational studies allows us to propose the likely role of the conserved tyrosine as a general base for proton abstraction in PsiS-catalyzed reaction as well as structural role of the hydrophobic phenol ring in the active site.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
