Abstract
Pineal acetylserotonin methyltransferase (ASMT) activity was studied in western fence lizards ( Sceloporus occidentalis) collected in May in Napa Co., California. Although pineal dry weight differed in the two age (size) classes of animals present (adults, 25.1 ± 1.6 μg; subadults, 16.1 ± 1.3 μg), pineal ASMT activity per unit weight did not differ. Thin-layer chromatography of extracts from enzyme incubations with N-acetylserotonin showed a single methylated product comparable to melatonin or 6-hydroxymelatonin. Different apparent ASMT activities were obtained in incubations with different buffer systems over the same pH range. Results suggest that phosphate buffer coupled with excess substrate concentrations and incubation temperature of 37°C is inhibitory to pineal ASMT in this species. Tris-HCl is shown to be the preferred buffer, and saturation concentrations of substrate and methyl donor are demonstrated.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: 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.
