Amur, SG and Paliyath, Gopinathan and Murthy, SK (1983) Temperature dependence of palmitoyl-CoA synthetase of chicken liver microsomes: Effect of Triton X-100 and lysophosphatidylcholine. In: Indian Journal of Biochemistry & Biophysics, 20 (3). pp. 141-145.
Full text not available from this repository. (Request a copy)Abstract
Palmitoyl-CoA synthetase (EC 6.2.1.3) of chicken liver microsomes showed a break in the Arrhenius plot of activity in the region $22-26^o$. This was abolished by Triton X-100 or lysophosphatidylcholine (LPC), individually or together, NMR spectra showed that the break in the Arrhenius plot of activity can be related to the phase transitions in the phospholipid bilayer structure of the microsomes. Even though Triton X-100 and(or) LPC lower the energy of activation (Ea), there was no correlation between the lowering of Ea and the extent of stimulation of the enzyme activity. The enzyme prepn. solubilized from the microsomes by Triton X-100 after removal of the detergent, did not exhibit any break in the Arrhenius plot of activity. However, the enzyme activity of this prepn. was also stimulated by Triton X-100 and(or) LPC but without substantial change in Ea. LPC had no effect on the Km for palmitate, whereas Triton X-100 increased it by 2-fold, but the Vmax of the reaction was increased by either compd. Triton X-100 or LPC may stimulate the enzyme activity by effecting conformational change(s) that do not involve an increase in the affinity of the enzyme for the substrate
Item Type: | Journal Article |
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Publication: | Indian Journal of Biochemistry & Biophysics |
Publisher: | National Institute of Science Communication and Information Resources |
Additional Information: | Copyright of this article belongs to NISCAIR. |
Department/Centre: | Division of Biological Sciences > Biochemistry |
Date Deposited: | 22 Jul 2008 |
Last Modified: | 27 Aug 2008 13:37 |
URI: | http://eprints.iisc.ac.in/id/eprint/15138 |
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