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A study of the enzymatic oligomerization of 5-hydroxytryptamine using matrix-assisted laser desorption/ionization mass spectrometry

✍ Scribed by Donata Favretto; Antonella Bertazzo; Carlo Costa; Graziella Allegri; Pietro Traldi

Publisher
John Wiley and Sons
Year
1997
Tongue
English
Weight
155 KB
Volume
11
Category
Article
ISSN
0951-4198

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✦ Synopsis

The role of tyrosinase in melanogenesis from 5-hydroxytryptamine was investigated by drawing samples from the reaction environment at different reaction times. Samples were ultrafiltered to remove the enzyme and lyophylized. In order to evaluate the role of non-enzymatic oxidation, a portion of the ultrafiltered samples was left to react under an oxygen stream for 24 hours prior to lyophilization. All the samples were analyzed by matrix-assisted laser desorption/ionization mass spectrometry. The formation of protonated tetramers was observed for samples immediately lyophilized, while further non-enzymatic reaction with bubbling oxygen led to formation of larger oligomers up to octamers. Clear analogies were observed between the data obtained on the enzymatic reaction and those reported in the literature on the electrochemically induced oxidation of 5-hydroxytryptamine.

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