Equilibrium and kinetic studies of the folding of the subunits of bactrial luciferase /
The subunits of Lucifers from Vibrio harveyi have been
| Main Author: | |
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| Format: | Thesis Book |
| Language: | English |
| Published: |
[Place of publication not identified] :
[publisher not identified] ;
1995.
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| Subjects: | |
| Online Access: | Link to OAKTrust copy http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=742145561&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | The subunits of Lucifers from Vibrio harveyi have been separately expressed and purified. Ultracentrifugation and subunit complementation revealed that the [] subunit was able to form a homodimer which was incapable of associating with the [] subunit to form active enzyme. Equilibrium denaturation showed that the heterodimer unfolded reversibly in urea with a free energy of stabilization around 24 kcal mol-1. A similar analysis for the []2 homodimer demonstrated a species which was kinetically very stable, and therefore exhibited dramatic hysteresis in the unfolding/refolding process. Analysis of the rates of folding and unfolding the homodimer indicated that the free energy of stabilization was not significantly different than the heterodimer. Two different conformations were shown to exist for folding [] subunit, one which was competent to associate with itself or with the a subunit to produce active enzyme, and a misfolded state which was prone to aggregation. High temperatures of refolding favored formation of the misfolded state so refolding experiments were limited to temperatures at or below 18. Conditions were found in which partial recovery of active enzyme could be achieved from refolding of thermally denatured subunits. |
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| Item Description: | Vita. "Major Subject: Biochemistry". |
| Physical Description: | xiii, 132 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references. |