Beaucamp, Nicola and Schurig, Hartmut and Jaenicke, Rainer (1997) The PGK-TIM fusion protein from Thermotoga maritima and its constituent parts are intrinsically stable and fold independently. BIOLOGICAL CHEMISTRY, 378 (7). pp. 679-685. ISSN 1431-6730, 1437-4315
Full text not available from this repository.Abstract
In the hyperthermophilic bacterium Thermotoga maritima, the two glycolytic enzymes phosphoglycerate kinase (PGK) and triosephosphate isomerase (TIM) are covalently connected forming a tetrameric single-chain PGK-TIM fusion protein. A frameshift allows the translation of PGK alone, whereas TIM activity exclusively resides in the fusion protein (Schurig et al., 1995). Cloning the pgk-tim gene from Thermotoga maritima in Escherichia coli, yields monomeric PGK and tetrameric PGK-TIM fusion protein as authentic recombinant proteins (Beaucamp et al., 1995). Both exhibit high intrinsic stability. The thermal transitions at approximate to 80 degrees C are irreversible, rendering determination of thermodynamic data impossible. The half-concentrations, (C-GdmCl)(1/2) Of the guanidinium-chloride induced unfolding transitions are 3.0 and 3.9 M GdmCl for PGK and the PGK-TIM fusion protein, respectively. Monitoring denaturation by activity, fluorescence emission and circular dichroism, deactivation and unfolding of the two-domain PGK is found to precede the transitions of the TIM domain. With increasing temperature, (C-GdmCl)(1/2) is shifted to lower denaturant concentrations; at the same time, the transitions change from bimodal to unimodal. As indicated by the incomplete reversibility of the deactivation/unfolding/dissociation transitions, misfolding, as well as wrong domain interactions seem to interfere with the correct folding and association of the bienzyme complex.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | SP-NOV REPRESENTS; TRIOSEPHOSPHATE ISOMERASE; PHOSPHOGLYCERATE KINASE; EVOLUTIONARY CONSERVATION; ENZYME; DEHYDROGENASE; RECONSTITUTION; CATALYSIS; STABILITY; SEQUENCE; glycolysis; PGK; thermostability; Thermotoga manitima; TIM |
| Subjects: | 500 Science > 540 Chemistry & allied sciences 500 Science > 570 Life sciences |
| Divisions: | Biology, Preclinical Medicine > Institut für Biophysik und physikalische Biochemie |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 25 Oct 2023 06:17 |
| Last Modified: | 25 Oct 2023 06:17 |
| URI: | https://pred.uni-regensburg.de/id/eprint/50705 |
Actions (login required)
 |
View Item |
