Abstract
Summary The activity of calmodulin-activated cyclic nucleotide phosphodies-terase in a standard reaction containing 40 ng calmodulin could be inhibited about 50% by 14 μM Triton x-100. In contrast, the calmodulin-independent phosphodiesterase required a much higher concentration of the detergent, 380 μM for 50% inhibition of its activity. The potent inhibitory effect of Triton X-100 on the calmodulin-activated phosphodiesterase reaction could be reversed by high concentrations of calmodulin. Using the gel filtration technique, it was demonstrated that 3 H-Triton X-100 bound to calmodulin with high affinity in buffer containing Ca 2+ . The binding of the detergent to calmodulin was mostly eliminated in the presence of trifluoperazine, a neuroleptic drug. Among other detergents examined, including Lubrol WX, Triton QS and Triton CF, only Triton CF exhibited preferential inhibition of the calmodulin-activated phosphodiesterase. The results suggest that certain detergents in the Triton family inhibit calmodulin action by undergoing Ca 2+ -dependent binding to the protein at the neuroleptic drug site.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Biochemical and Biophysical Research Communications
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.